chore: removing build dependencies and using testcontainers for container spin up

[aepfli]

This PR

Removing the need for local dependencies of buf and the need to run docker compose to run e2e tests.

The Docker container will automatically start, and buf files will be loaded via npm from buf.build as generated SDKs.

I tried to do the same thing for flagd, but the generated buf files via https://github.com/stephenh/ts-proto are not delivered as SDKs from buf.build. Hence, I can't remove the dependency on buf. If we finalize this approach, I will add the test-container execution.

to Verify run nx e2e providers-flagd-web locally, it should actually run without any docker spin ups

[toddbaert]

This is cool!

[toddbaert]

Will this clash with the CI's services? Would we need to disable those?

[aepfli]

Will this clash with the CI's services? Would we need to disable those?

it will not clash with ci services, and if we use testcontainers everywhere we should not need to have this ci services anymore - as our test will handle the containers, and more importantly provide better port mapping out of the box - see the java reference open-feature/java-sdk-contrib#860 - where we can actually skip the serlvices, and just configure the exposed port, and use the host port automatically (no port issues anymore)

[aepfli]

@toddbaert i kindly ask you to review this again.

i changed the way we build buf files, now it is just a npx command without any fancy directory changes, and file operations (just using the cli)

i removed all the setups for the e2e tests and added dedicated jest wrapper tests, which will handle the spin up and tear down of the container (those tests are a good starting point for #986) - due to that all previous tests are now exporting a function which is called via the wrapper tests.

it looks big, but it is not really complicated, please review if you do have time

[lukas-reining]

Great change and great to have Testcontainers in!

[toddbaert]

@aepfli this looks excellent to me. TBH of all our gherkin suites, I was the least happy with this one, this seems like a huge improvement. Thanks a lot. I left a few nits, and I want to check one or two things locally, but I think I'll approve soon.

[toddbaert]

Amazing. This is much nicer. Can't thank you enough! Event the console feedback is much more understandable now.

[toddbaert]

I've marked this as a chore, since it's only a "feature" for developers, not for the users of the flagd/flagd-web providers.