Bumped rexml to 3.2.5 (CVE-2021-28965).

Gemfile.lock

@@ -437,7 +437,7 @@ GEM
       mime-types (>= 1.16, < 4.0)
       netrc (~> 0.8)
     retriable (2.1.0)
-    rexml (3.2.4)
+    rexml (3.2.5)
     rspec-core (3.9.2)
       rspec-support (~> 3.9.3)
     rspec-expectations (3.9.2)