Bump websocket-extensions from 0.1.4 to 0.1.5

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>

Author: dependabot[bot]

Gemfile.lock

@@ -116,7 +116,7 @@ GEM
       mini_portile2 (~> 2.4.0)
     popper_js (1.16.0)
     public_suffix (4.0.3)
-    puma (3.12.3)
+    puma (3.12.6)
     rack (2.2.2)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -208,7 +208,7 @@ GEM
       railties (>= 5.0)
     websocket-driver (0.6.5)
       websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.4)
+    websocket-extensions (0.1.5)
     xpath (3.2.0)
       nokogiri (~> 1.8)