Tweak no version found error message

* So it ends with "Use ruby/setup-ruby@v1" which seems to be what some
  people miss.

Author: eregon

dist/index.js

@@ -150,8 +150,7 @@ function validateRubyEngineAndVersion(platform, engineVersions, engine, parsedVe
     } else {
       throw new Error(`Unknown version ${parsedVersion} for ${engine} on ${platform}
         available versions for ${engine} on ${platform}: ${engineVersions.join(', ')}
-        Make sure you use the latest version of the action with - uses: ruby/setup-ruby@v1
-        File an issue at https://github.com/ruby/setup-ruby/issues if you would like support for a new version`)
+        Make sure you use the latest version of the action with - uses: ruby/setup-ruby@v1`)
     }
   }