Build with Maven: Error - BookApplicationTests.contextLoads » IllegalState Failed to load ApplicationContext

Question

I have created a simple book REST API with Spring Boot.

BookController.java

@RestController
@RequestMapping("/api/books")
public class BookController {
    private final BookService bookService;

    @Autowired
    public BookController(BookService bookService) {
        this.bookService = bookService;
    }

    @PostMapping
    public ResponseEntity<Book> createBook(@RequestBody Book book) {
        Book createdBook = bookService.createBook(book);
        return new ResponseEntity<>(createdBook, HttpStatus.CREATED);
    }

    // other endpoints
}

Book.java

@Entity
public class Book {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long bookId;

    // other attributes
}

BookRepository.java

@Repository
public interface BookRepository extends JpaRepository<Book, Long> {
}

BookServiceImpl.java

@Service
public class BookServiceImpl implements BookService {
    private final BookRepository bookRepository;

    @Autowired
    public BookServiceImpl(BookRepository bookRepository) {
        this.bookRepository = bookRepository;
    }

    @Override
    public Book createBook(Book book) {
        return bookRepository.save(book);
    }

    // other methods
}

Now I have executed the test class BookApplicationTest.java:

@SpringBootTest
class BookApplicationTests {
    @Autowired
    private BookController bookController;

    @Test
    void contextLoads() {
        assertThat(bookController).isNotNull();
    }
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.2.3</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example.demo</groupId>
    <artifactId>book</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>book</name>
    <description>Demo project</description>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
        <version>2.2.224</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.mariadb.jdbc</groupId>
        <artifactId>mariadb-java-client</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
    </dependency>
    </dependencies>

    <build>
        <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
    </build>

</project>

application.properties

spring.datasource.url=jdbc:mariadb://localhost:3306/{DATABASE_NAME}
spring.datasource.username={DATABASE_USERNAME}
spring.datasource.password={DATABASE_PASSWORD}
spring.datasource.driver-class-name=org.mariadb.jdbc.Driver

spring.jpa.generate-ddl=true
spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.database-platform=org.hibernate.dialect.MariaDBDialect

If I start the class with IntelliJ, then the test is successful. But when I run it with GitHub Actions then "Build with Maven" says:

Errors: Error: BookApplicationTests.contextLoads » IllegalState Failed to load ApplicationContext for [WebMergedContextConfiguration@602c167e testClass = at.fhcw.se.book.BookApplicationTests, locations = [], classes = [at.fhcw.se.book.BookApplication], contextInitializerClasses = [], activeProfiles = [], propertySourceDescriptors = [], propertySourceProperties = ["org.springframework.boot.test.context.SpringBootTestContextBootstrapper=true"], contextCustomizers = [org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizer@6892b3b6, org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory$DuplicateJsonObjectContextCustomizer@449a4f23, org.springframework.boot.test.mock.mockito.MockitoContextCustomizer@0, org.springframework.boot.test.web.client.TestRestTemplateContextCustomizer@3e27ba32, org.springframework.boot.test.autoconfigure.actuate.observability.ObservabilityContextCustomizerFactory$DisableObservabilityContextCustomizer@1f, org.springframework.boot.test.autoconfigure.pr [INFO] Error: Tests run: 1, Failures: 0, Errors: 1, Skipped: 0

maven.yml

name: ci/cd flow

on:
  push:
    branches: [ "main", "dev" ]

jobs:
  build:
  
    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v3
    - name: Set up JDK 17
      uses: actions/setup-java@v3
      with:
        java-version: '17'
        distribution: 'temurin'
        cache: maven
    - name: Build with Maven
      run: mvn clean install
    # Optional: Uploads the full dependency graph to GitHub to improve the quality of Dependabot alerts this repository can receive
    - name: Update dependency graph
      uses: advanced-security/maven-dependency-submission-action@571e99aab1055c2e71a1e2309b9691de18d6b7d6

What do I have to change so that the GitHub Actions workflow does not fail but runs successfully?