Merge pull request #292 from remote-jp/dependabot/bundler/docs/rexml-3.3.2

Bump rexml from 3.2.8 to 3.3.2 in /docs

Author: yasulab

docs/Gemfile.lock

@@ -99,8 +99,8 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.2.8)
-      strscan (>= 3.0.9)
+    rexml (3.3.2)
+      strscan
     rouge (4.2.0)
     ruby-rc4 (0.1.5)
     safe_yaml (1.0.5)