Simple adjustment to run as non-root

[hkolvenbach]

This adjustment changes the user to dbeaver (which is already created earlier as part of the Dockerfile) to run the container in environments, where root access is restricted, for example Kubernetes with securityContext.runAsNonRoot: true.

Addresses #2290.

Note: I do not have full visibility in all dependencies of dbeaver/cloudbeaver so I am unsure how to test if root access is required by any component. A local test running cloudbeaver with these adjustments was successful.

[LonwoLonwo]

Hello @hkolvenbach

Thanks for your contribution! It was a helpful solution to the issue.

However, our team is also developing its own solution here: #3526.
Because we have a wide range of products and deployment options, numerous hidden issues cannot be taken care of solely for your PR purposes.
Anyway, thanks again for the attempt.

[hkolvenbach]

Hi @LonwoLonwo, thanks for reviewing my suggestion and your feedback. Is running as non-root a planned feature for cloudbeaver-ce? The PR #3526 seems to set the correct permissions for the executable, but is not setting the Docker user to dbeaver (i.e. the USER dbeaver line that I added in my PR is missing from #3526)(d3f78fe#diff-6ca13838ce6f722e84758eaa6113e1d883e0d97c81b9316989ce18c124fba85cR23)