Bump rexml from 3.2.6 to 3.3.2 (#360)

Bumps [rexml](https://github.com/ruby/rexml) from 3.2.6 to 3.3.2.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.2.6...v3.3.2)

---
updated-dependencies:
- dependency-name: rexml
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: jheikes515 <87785368+jheikes515@users.noreply.github.com>

Gemfile.lock

@@ -15,13 +15,15 @@ GEM
  base64 (>= 0.1.0)
  rack (~> 2.2, >= 2.2.4)
  rack-ssl-enforcer (0.2.9)
- rexml (3.2.6)
+ rexml (3.3.2)
+ strscan
  ruby2_keywords (0.0.5)
  sinatra (3.2.0)
  mustermann (~> 3.0)
  rack (~> 2.2, >= 2.2.4)
  rack-protection (= 3.2.0)
  tilt (~> 2.0)
+ strscan (3.1.0)
  thin (1.8.2)
  daemons (~> 1.0, >= 1.0.9)
  eventmachine (~> 1.0, >= 1.0.4)