fix(ci): update PR auto-assignment workflow to use pull_request event and improve fork handling

Related issue: pull_request_target vulnerability  (https://nx.dev/blog/s1ngularity-postmortem)

Author: web-flow

.github/workflows/pr-assigner.yml

@@ -1,7 +1,7 @@
 name: PR Auto-Assignment
 run-name: "Assigning reviewers for PR #${{ github.event.pull_request.number }}"
 on:
-  pull_request:
+  pull_request_target:
     types: [opened, reopened, synchronize]
     branches:
       - main
@@ -26,6 +26,6 @@ jobs:
         with:
           persist-credentials: false
 
-      - uses: netcracker/qubership-workflow-hub/actions/pr-assigner@0f2be042d7c833c6bf60df85732609b7991fb821 #2.0.0
+      - uses: netcracker/qubership-workflow-hub/actions/pr-assigner@b575bad3a0959c4e883bc34f9d055ff07fde2dbd #2.0.1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}