Bump rexml from 3.2.6 to 3.2.8 in the bundler group

Bumps the bundler group with 1 update: [rexml](https://github.com/ruby/rexml).


Updates `rexml` from 3.2.6 to 3.2.8
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](https://github.com/ruby/rexml/compare/v3.2.6...v3.2.8)

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

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

Gemfile.lock

@@ -392,7 +392,8 @@ GEM
     regexp_parser (2.9.0)
     reline (0.5.3)
       io-console (~> 0.5)
-    rexml (3.2.6)
+    rexml (3.2.8)
+      strscan (>= 3.0.9)
     rouge (4.2.1)
     rspec-collection_matchers (1.2.1)
       rspec-expectations (>= 2.99.0.beta1)
@@ -520,6 +521,7 @@ GEM
     ssrf_filter (1.1.2)
     stackprof (0.2.26)
     stringio (3.1.0)
+    strscan (3.1.0)
     telegraf (3.0.0)
     temple (0.10.3)
     terser (1.2.2)