⬆️ Bump rexml from 3.3.5 to 3.3.6

Bumps [rexml](https://github.com/ruby/rexml) from 3.3.5 to 3.3.6.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.3.5...v3.3.6)

---
updated-dependencies:
- dependency-name: rexml
  dependency-type: indirect
  update-type: version-update:semver-patch
...

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

Gemfile.lock

@@ -449,7 +449,7 @@ GEM
       actionpack (>= 5.2)
       railties (>= 5.2)
     retriable (3.1.2)
-    rexml (3.3.5)
+    rexml (3.3.6)
       strscan
     rollbar (3.5.2)
     rqrcode (2.2.0)