Build(deps-dev): Bump rexml from 3.2.5 to 3.2.6 (#3600)

Bumps [rexml](https://github.com/ruby/rexml) from 3.2.5 to 3.2.6.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.2.5...v3.2.6)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -332,7 +332,7 @@ GEM
     regexp_parser (2.8.1)
     request_store (1.5.1)
       rack (>= 1.4)
-    rexml (3.2.5)
+    rexml (3.2.6)
     rollbar (3.4.0)
     rspec (3.12.0)
       rspec-core (~> 3.12.0)