Bring back GitHub forbidden pattern

I fixed the auto-generated docs to not generate Github - so we can bring back the check to ensure that it's spelled as GitHub

.github/actions/spelling/line_forbidden.patterns

@@ -11,6 +11,9 @@
 # s.b. anymore
 \bany more[,.]
 
+# s.b. GitHub
+\bGithub\b
+
 # s.b. GitLab
 \bGitlab\b
 

SUMMARY.md

@@ -835,7 +835,7 @@
     * [Upgrade property's value to version](reference/recipes/jenkins/upgradeversionproperty.md)
     * [Use Jenkins API plugin instead of libraries](reference/recipes/jenkins/replacelibrarieswithapiplugin.md)
     * [Use commons-lang3 API Plugin](reference/recipes/jenkins/commonslang3toapiplugin.md)
-    * [Github](reference/recipes/jenkins/github/README.md)
+    * [GitHub](reference/recipes/jenkins/github/README.md)
       * [Add plugin developer team to CODEOWNERS](reference/recipes/jenkins/github/addteamtocodeowners.md)
     * [Migrate](reference/recipes/jenkins/migrate/README.md)
       * [Hudson](reference/recipes/jenkins/migrate/hudson/README.md)