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] <[email protected]>

Gemfile.lock

@@ -266,7 +266,7 @@ 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
     rouge (4.1.2)
     rspec-core (3.13.0)