Bump rexml from 3.3.0 to 3.3.3

Bumps [rexml](https://github.com/ruby/rexml) from 3.3.0 to 3.3.3.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.3.0...v3.3.3)

---
updated-dependencies:
- dependency-name: rexml
  dependency-type: indirect
...

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

Gemfile.lock

@@ -211,7 +211,7 @@ GEM
  http-cookie (>= 1.0.2, < 2.0)
  mime-types (>= 1.16, < 4.0)
  netrc (~> 0.8)
- rexml (3.3.0)
+ rexml (3.3.3)
  strscan
  roar (1.1.1)
  representable (~> 3.0)