Merge pull request #15989 from infosiftr/breakman

Pin `ruby-binstubs` test gems to fix `brakeman` breakage

test/tests/ruby-binstubs/Gemfile

@@ -1,3 +1,3 @@
 source 'https://rubygems.org'
-gem 'bundler-audit'
-gem 'brakeman'
+gem 'bundler-audit', '0.9.1'
+gem 'brakeman', '5.4.1'