Update tags and :next as we implement Ruby 3.0 semantics for Module#attr_*

Author: eregon

spec/tags/core/module/attr_accessor_tags.txt

@@ -0,0 +1 @@
+fails:Module#attr_accessor returns nil

spec/tags/core/module/attr_reader_tags.txt

@@ -0,0 +1 @@
+fails:Module#attr_reader returns nil

spec/tags/core/module/attr_tags.txt

@@ -0,0 +1 @@
+fails:Module#attr returns nil

spec/tags/core/module/attr_writer_tags.txt

@@ -0,0 +1 @@
+fails:Module#attr_writer returns nil

spec/truffleruby.mspec

@@ -96,6 +96,10 @@ class MSpecScript
     spec/ruby/core/mutex/owned_spec.rb
     spec/ruby/core/fiber/raise_spec.rb
     spec/ruby/core/process/status/wait_spec.rb
+    spec/ruby/core/module/attr_spec.rb
+    spec/ruby/core/module/attr_reader_spec.rb
+    spec/ruby/core/module/attr_writer_spec.rb
+    spec/ruby/core/module/attr_accessor_spec.rb
   ]
 
   set :tags_patterns, [