chore: Update actions/upload-artifact from v2 to v3 (openedx#33580)

v2 is giving warnings: ``` The following actions uses node12 which is deprecated and will be forced to run on node16: actions/upload-artifact@v2. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/ ```
eduNEXT · Oct 24, 2023 · d18bf2c · d18bf2c
1 parent b0a004d
commit d18bf2c
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/.github/actions/unit-tests/action.yml b/.github/actions/unit-tests/action.yml
@@ -27,7 +27,7 @@ runs:
 
     - name: save pytest warnings json file
       if: success()
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: pytest-warnings-json
         path: |