.github: Remove outdated pull request template

.github/PR-BUILD.md

@@ -1,18 +0,0 @@
-## How to test a PR build
-
-Please take into account, that RPCS3 build usually takes some time (about 15 mins), so you can't access a build if a PR was just submitted.
-
-- Open a PR you want to test
-- Scroll to the very bottom and locate the **Checks** section
-- Click on **Show all checks**
-	You are supposed to see something like this
-	![image](https://user-images.githubusercontent.com/10283761/116630952-2cd99e00-a94c-11eb-933e-986d6020ca92.png)
-- Click on __Details__ on either **Cirrus Linux GCC** or **Cirrus Windows**
-- Click **View more details on Cirrus CI** at the very bottom
-	![image](https://user-images.githubusercontent.com/10283761/116631111-5e526980-a94c-11eb-95f7-751e6f15e1ea.png)
-- Click on the download button for **Artifact** on the **Artifacts** block
-	![image](https://user-images.githubusercontent.com/10283761/116631322-bee1a680-a94c-11eb-89a3-be365783582e.png)
-
-- Congratulations! You are now downloading an RPCS3 build for that specific PR.
-
-__Please note that PR builds are not supposed to be stable because they contain new changesets.__

.github/PULL_REQUEST_TEMPLATE/1-default.md

@@ -1,3 +0,0 @@
-<!-- Please include a summary of the change and which issue is fixed. -->
-
-[How to test this PR](.github/PR-BUILD.md)