BundledGem.dummy_spec needs to checkout revision after cloning repository.

The current BundledGem.dummy_spec always called from master branch.
  It caused to CI faiulres like
  http://rubyci.s3.amazonaws.com/ubuntu/ruby-master/log/20230305T001003Z.fail.html.gz

defs/gmake.mk

@@ -354,7 +354,7 @@ $(srcdir)/.bundle/.timestamp/$(1).revision: \
 
 # The repository of minitest does not include minitest.gemspec because it uses hoe.
 # This creates a dummy gemspec.
-$(srcdir)/gems/src/$(1)/$(1).gemspec: \
+$(srcdir)/gems/src/$(1)/$(1).gemspec: $(srcdir)/.bundle/.timestamp/$(1).revision \
 	| $(srcdir)/gems/src/$(1)/.git
 	$(Q) $(BASERUBY) -I$(tooldir)/lib -rbundled_gem -e 'BundledGem.dummy_gemspec(*ARGV)' $$(@)