chore(deps-dev): Bump rexml from 3.3.6 to 3.3.9 (#2383)

Bumps [rexml](https://github.com/ruby/rexml) from 3.3.6 to 3.3.9.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.3.6...v3.3.9)

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

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

Gemfile.lock

@@ -401,8 +401,7 @@ GEM
       io-console (~> 0.5)
     request_store (1.7.0)
       rack (>= 1.4)
-    rexml (3.3.6)
-      strscan
+    rexml (3.3.9)
     rspec-core (3.13.1)
       rspec-support (~> 3.13.0)
     rspec-expectations (3.13.2)
@@ -502,7 +501,6 @@ GEM
       listen (>= 2.7, < 4.0)
       spring (>= 4)
     stringio (3.1.1)
-    strscan (3.1.0)
     sync (0.5.0)
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)