Merge pull request #1458 from adafruit/dependabot/bundler/rexml-3.3.6

Bump rexml from 3.3.3 to 3.3.6

Author: makermelissa

Gemfile.lock

@@ -69,7 +69,7 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.3.3)
+    rexml (3.3.6)
       strscan
     rouge (4.1.0)
     ruby-vips (2.1.4)