Bump websocket-extensions from 0.1.4 to 0.1.5 (heroku#65)

Bumps [websocket-extensions](https://github.com/faye/websocket-extensions-ruby) from 0.1.4 to 0.1.5.
- [Release notes](https://github.com/faye/websocket-extensions-ruby/releases)
- [Changelog](https://github.com/faye/websocket-extensions-ruby/blob/master/CHANGELOG.md)
- [Commits](faye/websocket-extensions-ruby@0.1.4...0.1.5)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -161,7 +161,7 @@ GEM
       execjs (>= 0.3.0, < 3)
     websocket-driver (0.7.1)
       websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.4)
+    websocket-extensions (0.1.5)
 
 PLATFORMS
   ruby