Drop a redundant slash

Author: k0kubun

bin/notes-github-pr.rb

@@ -92,7 +92,7 @@ def git(*cmd, repo_path: nil)
 
   Dir.mktmpdir do |workdir|
     depth = Git.rev_list("#{oldrev}..#{newrev}", repo_path: repo_path).size + 1
-    system('git', 'clone', "--depth=#{depth}", "--branch=#{branch}", "file:///#{repo_path}", workdir)
+    system('git', 'clone', "--depth=#{depth}", "--branch=#{branch}", "file://#{repo_path}", workdir)
     Dir.chdir(workdir)
     system('git', 'fetch', 'origin', 'refs/notes/commits:refs/notes/commits')