add suppressions for ruby 2.7

related to #1938

Author: flavorjones

suppressions/nokogiri_ruby-2.7.supp

@@ -0,0 +1,25 @@
+{
+ https://ci.nokogiri.org/teams/nokogiri-core/pipelines/nokogiri/jobs/ruby-2.7-rc-valgrind/builds/1
+ Memcheck:Addr8
+ fun:mark_locations_array
+ fun:gc_mark_stacked_objects
+ fun:gc_mark_stacked_objects_incremental
+ fun:gc_marks_rest
+ ...
+ fun:ruby_finalize_?
+ fun:ruby_cleanup
+ fun:ruby_run_node
+ fun:main
+}
+{
+ https://ci.nokogiri.org/teams/nokogiri-core/pipelines/nokogiri/jobs/ruby-2.7-rc-valgrind/builds/1
+ Memcheck:Addr8
+ fun:mark_locations_array
+ fun:gc_marks_wb_unprotected_objects
+ fun:gc_marks_finish
+ ...
+ fun:ruby_finalize_?
+ fun:ruby_cleanup
+ fun:ruby_run_node
+ fun:main
+}