Bump rdoc from 6.5.0 to 6.5.1.1

Bumps [rdoc](https://github.com/ruby/rdoc) from 6.5.0 to 6.5.1.1.
- [Release notes](https://github.com/ruby/rdoc/releases)
- [Changelog](https://github.com/ruby/rdoc/blob/master/History.rdoc)
- [Commits](ruby/rdoc@v6.5.0...v6.5.1.1)

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

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -252,7 +252,7 @@ GEM
       capybara (>= 2.1, < 4)
       cliver (~> 0.3.1)
       websocket-driver (>= 0.2.0)
-    psych (5.1.1)
+    psych (5.1.2)
       stringio
     public_suffix (5.0.3)
     racc (1.7.1)
@@ -298,7 +298,7 @@ GEM
     rainbow (3.1.1)
     raindrops (0.20.1)
     rake (13.0.6)
-    rdoc (6.5.0)
+    rdoc (6.5.1.1)
       psych (>= 4.0.0)
     regexp_parser (2.8.2)
     rest-client (2.1.0)
@@ -382,7 +382,7 @@ GEM
     sshkit (1.21.5)
       net-scp (>= 1.1.2)
       net-ssh (>= 2.8.0)
-    stringio (3.0.8)
+    stringio (3.1.1)
     terrapin (0.6.0)
       climate_control (>= 0.0.3, < 1.0)
     thor (1.2.2)