chore(deps): pin dependencies (#819)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
diff --git a/.github/workflows/pxc.yml b/.github/workflows/pxc.yml
index 305139e..964b993 100644
--- a/.github/workflows/pxc.yml
+++ b/.github/workflows/pxc.yml
@@ -26,7 +26,7 @@
     runs-on: v3-standard-8
     steps:
       - name: Checkout project
-        uses: actions/checkout@v4
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
 
       - name: Install Poetry
         run: pipx install poetry