Bump Ruby repo revision and deps version

The ruby repo is merged with the upstream master.  The modular GC has
been introduced upstream, and an experimental MMTk binding as a GC
module has been included in the official repo.

The ruby repo also fixed missing implementation of `memsize` and
`imemo_type_ids` for MMTk-specific types, excluded a few tests that
assume the behavior of the default GC, and implemented `GC.count`.

Author: wks

mmtk/Cargo.lock

@@ -12,7 +12,7 @@ edition = "2021"
 # Metadata for the Ruby repository
 [package.metadata.ci-repos.ruby]
 repo = "mmtk/ruby" # This is used by actions/checkout, so the format is "owner/repo", not URL.
-rev = "abce8f049f6eb231f8a605d576a16e1fff8ae86f"
+rev = "c2cd37133cf48d734eba697666dbf21ff4c4c39e"
 
 [lib]
 name = "mmtk_ruby"