Bump rexml from 3.3.6 to 3.3.9 (#19)

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

Gemfile.lock

@@ -24,8 +24,7 @@ GEM
     racc (1.7.1)
     rainbow (3.1.1)
     regexp_parser (2.8.2)
-    rexml (3.3.6)
-      strscan
+    rexml (3.3.9)
     rspec (3.12.0)
       rspec-core (~> 3.12.0)
       rspec-expectations (~> 3.12.0)
@@ -63,7 +62,6 @@ GEM
       rubocop-factory_bot (~> 2.22)
     ruby-progressbar (1.13.0)
     rubyzip (2.3.2)
-    strscan (3.1.0)
     thor (1.3.0)
     tomlrb (2.0.3)
     unicode-display_width (2.5.0)