Update webrick to version 1.8.2

Author: depfu[bot]

Gemfile.lock

@@ -129,7 +129,7 @@ GEM
     unicode-display_width (2.6.0)
     uri (0.13.1)
     version_gem (1.1.4)
-    webrick (1.8.1)
+    webrick (1.8.2)
     yard (0.9.37)
     yard-junk (0.0.10)
       backports (>= 3.18)