Exclude packages/ from ruby_wasm gem package

Author: kateinoigakukun

ruby_wasm.gemspec

@@ -21,7 +21,8 @@ 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(__dir__) do
     `git ls-files -z`.split("\x0").reject do |f|
-      (f == __FILE__) || f.match(%r{\A(?:(?:bin|test|spec|features)/|\.(?:git|travis|circleci)|appveyor)})
+      (f == __FILE__) || f.match(%r{\A(?:(?:bin|test|spec|features)/|\.(?:git|travis|circleci)|appveyor)}) ||
+        f.match(%r{\Apackages/})
     end
   end
   spec.bindir = "exe"