Update to Ruby 3

[jhernand]

Currently the SDK doesn't build or work with Ruby 3:

• The code generator needs at least Weld 3 in order to work with Java 11.

• The versions of rake, rubocop and webrick need to be udpated to work with Ruby 3.

• The C code needs to be udpated to use the rb_thread_call_with_gvl only when the code doesn't already hold the GVL. This is probably due to changes in libcurl.

This patch contains fixes for all those issues.

[jhernand]

Not that this will also need a new version of the API metamodel containing this change: oVirt/ovirt-engine-api-metamodel#34

[kbrock]

Would it be easier to merge if we split this PR apart?
e.g.: the rubocop changes seem like a no brainer

Or is the issue that there just isn't much time and multiple PRs are actually more difficult?

[kbrock]

I pulled the c code fix and put into #17 (kept attribution)

[kbrock]

@sandrobonazzola FYI - your commit does not have signoff

[sandrobonazzola]

@sandrobonazzola FYI - your commit does not have signoff

I just hit rebase :-)
@jhernand / @eremeyev can you fix commit message with missing sign off?

[mwperina]

The problem with this change is, that weld 3 super hard to package as RPM due to missing dependencies, that's why we are still using weld 2.y. If we merge this PR before weld 3.y is available as RPM on cbs.centos.org, build process will be completely broken:

https://cbs.centos.org/koji/packageinfo?packageID=8971

[kbrock]

@mwperina thank you

Can we take the weld changes out of here? (and put into another PR)
So this would be mergable?

UPDATE: I created #19 which contains the ruby changes but not the Weld changes
Any little bit of progress is still progress