🙈 Exclude .mailmap and .github files from gem

Author: nevans

net-imap.gemspec

@@ -27,7 +27,7 @@ Gem::Specification.new do |spec|
   # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
   spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
     `git ls-files -z 2>/dev/null`.split("\x0")
-      .reject {|f| f.match(%r{^(bin|test|spec|benchmarks|features|rfcs)/}) }
+      .grep_v(%r{^(\.git|\.mailmap|bin|test|spec|benchmarks|features|rfcs)/})
   end
   spec.bindir        = "exe"
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }