Updated issue template about pull requests for fixes to docs.

Thanks to xet7 !

.github/ISSUE_TEMPLATE.md

@@ -2,6 +2,8 @@
 
 UPGRADE OR MIGRATE: https://github.com/wekan/wekan/blob/main/docs/Upgrade/Upgrade.md
 
+Pull requests welcome to fix any broken links at docs directory, and organizing docs/Features and their screenshots to subdirectories of each feature.
+
 Please report these issues elsewhere:
 
 - SECURITY ISSUES, PGP EMAIL: https://github.com/wekan/wekan/blob/main/SECURITY.md