chore(deps): update github actions to v4

Author: renovate-bot

.github/workflows/assign-issues.yml

@@ -25,7 +25,7 @@ jobs:
       issues: write
     steps:
       - name: "Auto-assign issue"
-        uses: pozil/auto-assign-issue@v2
+        uses: pozil/auto-assign-issue@07fe6dc0e9771842b428f5739098d6140734e226 # v4.0.0
         with:
           assignees: dolphin1999,isaurabhuttam,prernakakkar-google
           numOfAssignee: 1

.github/workflows/assign-prs.yml

@@ -26,7 +26,7 @@ jobs:
       pull-requests: write
     steps:
       - name: "Auto-assign PR"
-        uses: pozil/auto-assign-issue@v2
+        uses: pozil/auto-assign-issue@07fe6dc0e9771842b428f5739098d6140734e226 # v4.0.0
         with:
           assignees: dolphin1999,isaurabhuttam,prernakakkar-google
           numOfAssignee: 1