Merge pull request #1627 from coderdojo-japan/dependabot/bundler/rexml-3.3.6

Bump rexml from 3.3.5 to 3.3.6

Author: yasulab

Gemfile.lock

@@ -371,7 +371,7 @@ GEM
     retriable (3.1.2)
     reverse_markdown (2.1.1)
       nokogiri
-    rexml (3.3.5)
+    rexml (3.3.6)
       strscan
     rspec-core (3.13.0)
       rspec-support (~> 3.13.0)