Bump rexml from 3.2.5 to 3.2.8 (#26)

Bumps [rexml](https://github.com/ruby/rexml) from 3.2.5 to 3.2.8.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.2.5...v3.2.8)

---
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

@@ -18,7 +18,8 @@ GEM
     rdoc (6.4.0)
       psych (>= 4.0.0)
     regexp_parser (2.2.1)
-    rexml (3.2.5)
+    rexml (3.2.8)
+      strscan (>= 3.0.9)
     rubocop (1.25.1)
       parallel (~> 1.10)
       parser (>= 3.1.0.0)
@@ -32,6 +33,7 @@ GEM
       parser (>= 3.1.1.0)
     ruby-progressbar (1.11.0)
     stringio (3.0.6)
+    strscan (3.1.0)
     unicode-display_width (2.1.0)
 
 PLATFORMS