chore(deps): bump rexml from 3.3.3 to 3.3.6 in /docs (#5717)

Bumps [rexml](https://github.com/ruby/rexml) from 3.3.3 to 3.3.6.

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

Author: dependabot[bot]

docs/Gemfile.lock

@@ -60,7 +60,7 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.3.3)
+    rexml (3.3.6)
       strscan
     rouge (4.2.0)
     safe_yaml (1.0.5)