Add documentation update pull request template

Author: asong56

.github/PULL_REQUEST_TEMPLATE/documentation.md

@@ -0,0 +1,22 @@
+## Documentation Update
+
+<!-- Describe what was wrong, missing, or unclear, and what you changed. -->
+
+Closes #
+
+---
+
+## What Changed
+
+| Location | Before | After |
+|----------|--------|-------|
+| <!-- e.g. README.md §Setup --> | <!-- what it said --> | <!-- what it says now --> |
+
+---
+
+## Checklist
+
+- [ ] All links are working
+- [ ] Code examples are accurate and tested where relevant
+- [ ] Spelling and grammar have been reviewed
+- [ ] No unrelated changes (code, config, etc.) are included in this PR