ci: manifest action avoid checkout of PR head

See zephyrproject-rtos/zephyr@5574a81
for more details.

Signed-off-by: Kari Hamalainen <kari.hamalainen@nordicsemi.no>

Author: karhama

.github/workflows/manifest.yml

@@ -11,10 +11,9 @@ jobs:
     name: Manifest
     steps:
       - name: Checkout the code
-        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
         with:
           path: ncs/nrf-bm
-          ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 0
           persist-credentials: false
 
@@ -29,7 +28,7 @@ jobs:
           west init -l . || true
 
       - name: Manifest
-        uses: zephyrproject-rtos/action-manifest@ea38f222cddfbbb9debb5f0239f4139ae2677ebb # v1.8.0
+        uses: zephyrproject-rtos/action-manifest@09983f53d3d878791aa37a7755ae44d695f4c1e5 # v2.0.0
         with:
           github-token: ${{ secrets.NCS_GITHUB_TOKEN }}
           manifest-path: 'west.yml'