Why does Gradle fail to build a working configuration?

Help/Discuss
1 
  #11 [build_backend 6/6] RUN chmod +x ./gradlew;     ./gradlew --no-daemon bo...
14:06:50
  #11 122.1
14:06:50
  #11 122.1 FAILURE: Build failed with an exception.
14:06:50
  #11 122.1
14:06:50
  #11 122.1 * What went wrong:
14:06:50
  #11 122.1 Could not determine the dependencies of task ':app:bootJar'.
14:06:50
  #11 122.1 > Could not resolve all task dependencies for configuration ':app:runtimeClasspath'.
14:06:50
  #11 122.1    > Could not resolve project :shared-app.
14:06:50
  #11 122.1      Required by:
14:06:50
  #11 122.1          project :app
14:06:50
  #11 122.2       > No matching configuration of project :shared-app was found. The consumer was configured to find a runtime of a library compatible with Java 15, packaged as a jar, and its dependencies declared externally, as well as attribute 'org.jetbrains.kotlin.platform.type' with value 'jvm' but:
14:06:50
  #11 122.2           - None of the consumable configurations have attributes.
14:06:50
  #11 122.2
14:06:50
  #11 122.2 * Try:
14:06:50
  #11 122.2 Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
14:06:50
  #11 122.2
14:06:50
  #11 122.2 * Get more help at https://help.gradle.org

I have no idea what that is supposed to mean.

The build always goes fine locally, but whenever I want the CI pipeline to build it into a Docker image, I get the above error.

I want to know what the errors mean, independent of my build.gradle.kts. What do these errors mean? What do I have to fix, even though the build runs fine locally?