Update ruby and mmtk-core repos revision

Updated mmtk-core to the latest master.

The ruby repo is merged with the upstream master.  We reverted the
change of IMEMO type mask size because another flag OBJ_FIELD_HEAP is
required to have the same value as OBJ_FIELD_HEAP.

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 = "fe51e6277b4df810a90c4474f951ed0a263acea0"
+rev = "e4f5cb73824dd411c0cb1cf12aca42996f427da3"
 
 [lib]
 name = "mmtk_ruby"
@@ -37,7 +37,7 @@ features = ["is_mmtk_object", "object_pinning", "sticky_immix_non_moving_nursery
 
 # Uncomment the following lines to use mmtk-core from the official repository.
 git = "https://github.com/mmtk/mmtk-core.git"
-rev = "6eb1328bfce34a7e0fc4b84fd0b65a849b083e0e"
+rev = "ef153615d115edf196c0df2029e4340468276372"
 
 # Uncomment the following line to use mmtk-core from a local repository.
 #path = "../../mmtk-core"