Bump rexml from 3.2.6 to 3.3.3

Bumps [rexml](https://github.com/ruby/rexml) from 3.2.6 to 3.3.3.
- [Release notes](https://github.com/ruby/rexml/releases)
- [Changelog](https://github.com/ruby/rexml/blob/master/NEWS.md)
- [Commits](ruby/rexml@v3.2.6...v3.3.3)

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

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -24,7 +24,8 @@ GEM
       method_source (~> 1.0)
       spoon (~> 0.0)
     public_suffix (5.0.3)
-    rexml (3.2.6)
+    rexml (3.3.3)
+      strscan
     rspec-core (3.12.2)
       rspec-support (~> 3.12.0)
     rspec-expectations (3.12.3)
@@ -42,6 +43,8 @@ GEM
     simplecov_json_formatter (0.1.4)
     spoon (0.0.6)
       ffi
+    strscan (3.1.0)
+    strscan (3.1.0-java)
     webmock (3.18.1)
       addressable (>= 2.8.0)
       crack (>= 0.3.2)