Upgrade R2DBC implementation classes for spring boot 2.4

[ecostanzi]

Fixes #13613

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[ecostanzi]

Tests for a project without entities should pass. Currently working on single entity repositories.

[ecostanzi]

I still have to clean up imports and some constructor, but webflux sql tests are passing now. I'll continue tomorrow.

[mraible]

@ecostanzi It seems that all tests are passing! I think the npm test failure is caused by something else.

You could test some more databases by enabling them in the CI job for this branch.

https://github.com/jhipster/generator-jhipster/blob/main/.github/workflows/webflux.yml#L142

I recommend using sqllight for the entity property. That way, e2e tests are a bit faster.

[ecostanzi]

@mraible I think it's ready for the review. I added the tests as you suggested. I also tested it locally using blog-oauth2.jdl with the reactive option and it seems to work correctly. Feel free to suggest more tests if they're needed.

[mraible]

Well done, @ecostanzi! 🙌

[ecostanzi]

thanks @mshima I didn't noticed :/

[mraible]

Please merge when CI passes!

[ecostanzi]

With mariadb integration tests with testcontainers don't work, I disabled testcontainers. With mysql integration tests pass, but I noticed some e2e test failures that don't seem to be related to the backend. Have we ever seen them working? I saw that they were both been disabled for similar reasons(see 361fab2 and 6fcbb1e).

[mraible]

I'm merging. If there are remaining issues, we can clean them up in the spring-boot-2.4 branch.