chore(deps): Update actions/cache action to v5 (#2425)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/cache](https://redirect.github.com/actions/cache) | action | major | `v4` → `v5` |

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### Release Notes

<details>
<summary>actions/cache (actions/cache)</summary>

### [`v5`](https://redirect.github.com/actions/cache/compare/v4...v5)

[Compare Source](https://redirect.github.com/actions/cache/compare/v4...v5)

</details>

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### Configuration

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🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update again.

---

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Author: cq-bot

.github/workflows/gen_coverage_report.yml

@@ -28,7 +28,7 @@ jobs:
           go-version: "1.26"
           cache: false
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~/go/pkg/mod

.github/workflows/go_mod_tidy_examples.yml

@@ -27,7 +27,7 @@ jobs:
           go-version-file: go.mod
           cache: false
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~/go/pkg/mod

.github/workflows/lint_golang.yml

@@ -23,7 +23,7 @@ jobs:
           go-version-file: go.mod
           cache: false
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~/go/pkg/mod

.github/workflows/unittest.yml

@@ -33,7 +33,7 @@ jobs:
           echo "gocache=$(go env GOCACHE)" >> "$GITHUB_OUTPUT"
           echo "gomodcache=$(go env GOMODCACHE)" >> "$GITHUB_OUTPUT"
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ${{ steps.go-cache.outputs.gomodcache }}