Dockerfile improvements

[dennisvang]

The Dockerfile explicitly specifies the production profile and corresponding application config files:

FAIRDataPoint/Dockerfile.build

Lines 40 to 42 in 75013ff

	COPY --from=builder /builder/target/classes/application-production.yml /fdp/application.yml
	ENTRYPOINT java -jar app.jar --spring.profiles.active=production --spring.config.location=classpath:/application.yml,classpath:/application-production.yml,file:/fdp/application.yml

This makes life difficult if we want to run the container with a different profile, as in the following:

• FDP in the latest (develop) docker image cannot start #581

It would be more convenient to allow specifying the profile using environment variables.

While we're at it, perhaps we could introduce some optimizations and security improvements, as suggested in the spring-boot docs etc.

• profiles using env variables (also see externalized configuration)

• don't run as root

• efficient container image (probably requires github actions cache to make a difference)

          uses: docker/build-push-action@v6
          with:
            ...           
            cache-from: type=gha
            cache-to: type=gha,mode=max