ci: update IssueLens triage action timeout

Pin issue-loop to the timeout-fixed revision from microsoft/IssueLens#53, increasing stream inactivity tolerance to 300 seconds without changing the 15-minute total read budget.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: chagong

.github/workflows/issuelens-run.yml

@@ -35,7 +35,7 @@ jobs:
       id-token: write
     steps:
       - name: Run IssueLens issue loop
-        uses: microsoft/IssueLens/.github/actions/issuelens@49df3d97547069f891a68248be6ed722c2aeca2f
+        uses: microsoft/IssueLens/.github/actions/issuelens@a81d2d96167fc0e69ac631c2edc85f858e693289
         with:
           request-type: issue-loop
           issue-number: ${{ inputs.issue_number }}