Ruby

[DOC] Remove an obsolete file

It has been merged into doc/ruby/options.md with
field_processing.md at ruby/ruby#10138.

refactor io_each_codepoint

[Doc] Remove leftover references to namespace from box.md

And fix the indentation a little bit, since box is one character
longer than ns.

ZJIT: Add individual tests for complex arg pass counters

Make it easier to see what happens when one is changed.

Add rubygems package to fix cygwin CI

Skip tests in TestThreadLockNativeThread when using LSAN

These tests use NM threads but NT is not freed for MN thread, causing it
to be reported as memory leaks in LSAN. For example:

#1 0x62ee7bc67e99 in calloc1 gc/default/default.c:1495:12
#2 0x62ee7bc7ba00 in rb_gc_impl_calloc gc/default/default.c:8216:5...

ZJIT: Support JIT-to-JIT calls to callees with optional parameters

• Correct JIT entry points for optionals so each optional start with nil
  before their initialization routine runs. Establish
  jit_entry_points[filled_opts_num] gives the appropriate entry point...

ZJIT: Check argument count matches callee's parameters

ZJIT: Remove done TODO [ci skip]

ZJIT: Remove dead function and set .freeze reason