Remove old ruby workarounds

Author: pirj

spec/rspec/core/metadata_spec.rb

@@ -13,7 +13,7 @@ module Core
         it "returns nil if passed an unparseable file:line combo" do
           expect(Metadata.relative_path("-e:1")).to be_nil
         end
-        # I have no idea what line = line.sub(/\A([^:]+:\d+)$/, '\\1') is supposed to do
+
         it "gracefully returns nil if run in a secure thread" do
           # Ensure our call to `File.expand_path` is not cached as that is the insecure operation.
           Metadata.instance_eval { @relative_path_regex = nil }

spec/support/helper_methods.rb

@@ -1,5 +1,5 @@
 module RSpecHelpers
-  SAFE_LEVEL_THAT_TRIGGERS_SECURITY_ERRORS = RUBY_VERSION >= '2.3' ? 1 : 3
+  SAFE_LEVEL_THAT_TRIGGERS_SECURITY_ERRORS = 1
   SAFE_IS_GLOBAL_VARIABLE = RUBY_VERSION >= '2.6'
 
   def relative_path(path)