Update PR template for preview and comment unnecessary text (#178)

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,12 +1,13 @@
-# Pull Request Template
+## Notion card
 
-## Description
-
-Please include a summary of the change and which issue is fixed. Please also
+## Summary
+<!-- Please include a summary of the change and which issue is fixed. Please also
 include relevant motivation and context. List any dependencies that are required
-for this change.
+for this change. -->
 
-Fixes # (issue)
+## Preview
+<!-- Please include a short loom video previewing the changes made in the PR. This will help
+the reviewers visualize and get context at a glance -->
 
 ## Type of change
 
@@ -24,7 +25,7 @@ Please delete options that are not relevant.
 instructions so we can reproduce. Please also list any relevant details for your
 test configuration -->
 
-## Checklist:
+### Checklist:
 
 - [ ] I have manually tested all workflows
 - [ ] I have performed a self-review of my own code