Run unit tests on external pull requests (#437)

* Run unit tests on external pull requests

* Prevent duplicate runs for internal branch PRs

* Update changelog

Co-authored-by: Michael Chin <chnmch@amazon.com>

Author: michaelnchin

.github/workflows/unit.yml

@@ -1,10 +1,16 @@
 name: Unit Tests
 
-on: [push]
+on:
+  push:
+    branches:
+      - '**'
+  pull_request:
+    branches:
+      - main
 
 jobs:
   unit-tests:
-
+    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2

ChangeLog.md

@@ -13,6 +13,7 @@ Starting with v1.31.6, this file will contain a record of major features and upd
 - Excluded certain `itables` versions causing errors in query magics ([PR #1](https://github.com/aws/graph-notebook/pull/429)) ([PR #2](https://github.com/aws/graph-notebook/pull/429))
 - Pinned version ceiling for all dependencies ([Link to PR](https://github.com/aws/graph-notebook/pull/431))
 - Truncated metadata request/query time metrics ([Link to PR](https://github.com/aws/graph-notebook/pull/425))
+- Enabled unit test workflow runs for external pull requests ([Link to PR](https://github.com/aws/graph-notebook/pull/437))
 
 ## Release 3.7.0 (December 7, 2022)
 - Added Neo4J section to `%%graph_notebook_config` ([Link to PR](https://github.com/aws/graph-notebook/pull/331))