Backport workflow-hardening fix (unpinned-uses) to 5 release branches

[CharlieMCY]

Summary

The default branch already hardened .github/workflows/alpha-releases.yaml against the issue(s) below, but 5 release branches still carry it. This proposes the same, minimal, scanner-verified fix for each.

What's flagged (by zizmor)

• unpinned-uses — actions referenced by mutable tag/branch instead of a pinned commit SHA

Already resolved on the default branch in:

• c88aa75

Affected release branches (5)

• release/yolo-mode (still present as of HEAD a2669cf1)
• release/light-client (still present as of HEAD 60b943fd)
• release/serving-bundle-fix (still present as of HEAD 0585e327)
• release/optional-deposit-snapshot (still present as of HEAD 6f088184)
• release/electra (still present as of HEAD 632a2b47)

Suggested per-branch patches

Each diff below was checked locally with zizmor and actionlint: the flagged finding(s) are cleared on the affected construct and no new lint or security findings are introduced. (Whitespace is normalized; only security-relevant lines change.)

release/yolo-mode — unpinned-uses

File .github/workflows/alpha-releases.yaml; suggested edits:

• ~ jobs.$J.steps[uses=actions/checkout].uses : pin(actions/checkout -> target_ref SHA)

--- a/.github/workflows/alpha-releases.yaml
+++ b/.github/workflows/alpha-releases.yaml
@@ -10,7 +10,7 @@
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744  # v3
         with:
           fetch-depth: 0
           ref: ${{ github.ref }}

release/light-client — unpinned-uses

File .github/workflows/alpha-releases.yaml; suggested edits:

• ~ jobs.$J.steps[uses=actions/checkout].uses : pin(actions/checkout -> target_ref SHA)

--- a/.github/workflows/alpha-releases.yaml
+++ b/.github/workflows/alpha-releases.yaml
@@ -10,7 +10,7 @@
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744  # v3
         with:
           fetch-depth: 0
           ref: ${{ github.ref }}

release/serving-bundle-fix — unpinned-uses

File .github/workflows/alpha-releases.yaml; suggested edits:

• ~ jobs.$J.steps[uses=actions/checkout].uses : pin(actions/checkout -> target_ref SHA)

--- a/.github/workflows/alpha-releases.yaml
+++ b/.github/workflows/alpha-releases.yaml
@@ -10,7 +10,7 @@
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744  # v3
         with:
           fetch-depth: 0
           ref: ${{ github.ref }}

release/optional-deposit-snapshot — unpinned-uses

File .github/workflows/alpha-releases.yaml; suggested edits:

• ~ jobs.$J.steps[uses=actions/checkout].uses : pin(actions/checkout -> target_ref SHA)

--- a/.github/workflows/alpha-releases.yaml
+++ b/.github/workflows/alpha-releases.yaml
@@ -10,7 +10,7 @@
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744  # v3
         with:
           fetch-depth: 0
           ref: ${{ github.ref }}

release/electra — unpinned-uses

File .github/workflows/alpha-releases.yaml; suggested edits:

• ~ jobs.$J.steps[uses=actions/checkout].uses : pin(actions/checkout -> target_ref SHA)

--- a/.github/workflows/alpha-releases.yaml
+++ b/.github/workflows/alpha-releases.yaml
@@ -10,7 +10,7 @@
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744  # v3
         with:
           fetch-depth: 0
           ref: ${{ github.ref }}

---

Happy to open pull requests instead if that's preferred.