Revert "Add support for PR and Issue templates to QMK_firmware GitHub (#4491)" (#4492)

This reverts commit b91dfa04e3.

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,22 +0,0 @@
-## Code Change Type
-- [ ] Core
-- [ ] Feature
-- [ ] Bugfix
-- [ ] Keyboard
-- [ ] Keymap/Layout/Userspace
-- [ ] Enhancement/Optimization
-- [ ] Documentation
-
-## Description
-A few sentences describing the overall goals of the pull request's commits.
-
-## Todo
-- [ ] Tests
-- [ ] Documentation
-
-## Issues Fixed or Closed by this PR
-
-* 
-
-## Long Description
-If needed, a longer description and a list of changes should be added here to make it clear what exactly this PR's goals are.