chore(deps): pin dependencies (googleapis#2699)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/checkout](https://redirect.github.com/actions/checkout) |
action | pinDigest | → `34e1148` |
|
[actions/download-artifact](https://redirect.github.com/actions/download-artifact)
| action | pinDigest | → `d3f86a1` |
|
[actions/upload-artifact](https://redirect.github.com/actions/upload-artifact)
| action | pinDigest | → `ea165f8` |

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Co-authored-by: Yuan Teoh <45984206+Yuan325@users.noreply.github.com>

Author: 2 people

.github/workflows/docs_preview_build.yaml

@@ -77,7 +77,7 @@ jobs:
           echo $PR_NUMBER > ../artifact-payload/pr_number.txt
 
       - name: Upload Artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4
         with:
           name: docs-preview-data
           path: artifact-payload/

.github/workflows/docs_preview_deploy.yaml

@@ -45,10 +45,10 @@ jobs:
       cancel-in-progress: true
     steps:
       - name: Checkout base repository
-        uses: actions/checkout@v4 
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4 
 
       - name: Download Artifact
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4
         with:
           name: docs-preview-data
           github-token: ${{ secrets.GITHUB_TOKEN }}