Update dependabot configuration

[DavideD]

Fix #1136

Built on top of #2341
Includes:

• Update project dependencies
• Update images in Dockerfile files under tooling/docker/
• Update images we use as services in the GitHub workflow (mysql and
  postgres to test the examples)

@marko-bekhta, could you have a look at the dependabot configuration in this commit and let me know if it makes sense?

[marko-bekhta]

nice 🎉

it's a shame that those more specialized containers do not allow for just passing the new ImageFromDockerfile. But your parsing logic looks good 😉 so let's give it a try 😃

[DavideD]

it's a shame that those more specialized containers do not allow for just passing the new ImageFromDockerfile. But your parsing logic looks good 😉 so let's give it a try 😃

I was thinking of sending a PR to Testcontainers when I have a little time to look into it.

My orignal plan was to actually keep all the configuration directly in the file because it also makes it easier for people to start a machine without using Testcontainers, but I think we can experiment with it for the future.