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

This reverts commit b91dfa04e3.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,27 +0,0 @@
----
-name: Bug report
-about: Create a report to help us improve the QMK Firmware
----
-
-**Describe the bug**
-
-A clear and concise description of what the bug is.
-
-**System Information**
- - Keyboard:  
-   - Revision (if applicable):  
- - Operating System:
- - avr-gcc version: 
-   (Run `avr-gcc --version` to find out)
- - arm gcc version: 
-   (Run `arm-none-eabi-gcc --version` to find out)
- - QMK Firmware version:
-   (you can run `git describe --abbrev=0 --tags` to find this out)
- - Any keyboard related software installed? 
-   - [ ] Auto Hot Key
-   - [ ] Karabiner
-   - [ ] Other
-
-**Additional context**
-
-Add any other context about the problem here.