Bump webrick from 1.7.0 to 1.8.2

Bumps [webrick](https://github.com/ruby/webrick) from 1.7.0 to 1.8.2.
- [Release notes](https://github.com/ruby/webrick/releases)
- [Commits](ruby/webrick@v1.7.0...v1.8.2)

---
updated-dependencies:
- dependency-name: webrick
  dependency-type: indirect
...

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

Gemfile.lock

@@ -601,7 +601,7 @@ GEM
       rack-proxy (>= 0.6.1)
       railties (>= 5.2)
       semantic_range (>= 2.3.0)
-    webrick (1.7.0)
+    webrick (1.8.2)
     websocket (1.2.10)
     websocket-driver (0.7.6)
       websocket-extensions (>= 0.1.0)