Ruby: support conan v2 and expose more configuration options for native extension gems

[jmarrec]

Ruby: support conan v2 and expose more configuration options for native extension gems

Reboots:

• #12455 - ruby/3.1.0: expose more configuration options for native extension gems #12456
• ruby: conan v2 support #12208

Both PRs were opened more than a year ago and got stale and closed.

Changelog (old commit messages):

• conan v2 support (work done by myself + a merge of @SpaceIm 's branch from PR ruby: conan v2 support #12208 to reconcile both)

• Extend testing to require one of the native extensions

* Use `--with-opt-dir` instead of `--with-xx-dir` that ruby isn't respecting.

conanio/gccXX (eg 10) removed the libxxx-dev (eg libgmp-dev) from the image. This made me realize that the conan deps weren't being picked up by the build. The openssl was, because --with-openssl-dir is explicitly used in ruby config.

So here, we rely on --with-opt-dir.

cf: https://bugs.ruby-lang.org/issues/19014#change-99241 (--with-gmp-dir was added on September 14, 2022, wrote this in Sep 22, 2022)

* Pass both --with-opt-dir and --with-xxx-dir

https://gist.github.com/mrkn/6647630

Specify library name and version:  **lib/1.0**

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- [x] I've read the [contributing guidelines](https://github.com/conan-io/conan-center-index/blob/master/CONTRIBUTING.md).
- [x] I've used a [recent](https://github.com/conan-io/conan/releases/latest) Conan client version close to the [currently deployed](https://github.com/conan-io/conan-center-index/blob/master/.c3i/config_v1.yml#L6). 
     - **Tested 1.60.1 and 2.0.7 locally**
- [x] I've tried at least one configuration locally with the [conan-center hook](https://github.com/conan-io/hooks.git) activated.