Bump rexml from 3.3.6 to 3.3.9 (#681)

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

@@ -272,8 +272,7 @@ GEM
     regexp_parser (2.9.2)
     reline (0.5.9)
       io-console (~> 0.5)
-    rexml (3.3.6)
-      strscan
+    rexml (3.3.9)
     rollbar (3.5.2)
     rubocop (1.65.1)
       json (~> 2.3)
@@ -343,7 +342,6 @@ GEM
     stimulus-rails (1.3.4)
       railties (>= 6.0.0)
     stringio (3.1.1)
-    strscan (3.1.0)
     temple (0.10.3)
     thor (1.3.1)
     tilt (2.3.0)