Erro na área de detalhes do Spring Boot Admin

No meu Spring Boot Admin mostra apenas alguns detalhes bem básicos da minha aplicação como, por exemplo: "Info", "Metadata" e "Health". Após isso apresenta o seguinte erro:

Meu arquivo de propriedade do forum:

--- Somente as relevantes para o tópico. ---

# actuator
management.endpoint.health.show-details=always
management.endpoints.web.exposure.include=*
info.app.name=@project.name@
info.app.description=@project.description@
info.app.version=@project.version@
info.app.encoding=@project.build.sourceEncoding@
info.app.java.version=@java.version@

# spring boot admin server
spring.boot.admin.client.url=http://localhost:8081

Dependências no pom.xml do forum:

--- Somente as relevantes para o tópico. ---

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>

    <dependency>
        <groupId>de.codecentric</groupId>
        <artifactId>spring-boot-admin-starter-client</artifactId>
        <version>2.4.3</version>
    </dependency>
</dependencies>

Dependências no pom.xml do Spring Boot Admin:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <dependency>
        <groupId>de.codecentric</groupId>
        <artifactId>spring-boot-admin-starter-server</artifactId>
        <version>2.4.3</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

Obs: Estou usando o Spring na versão 2.6.2.