chore(deps): update peter-evans/create-issue-from-file action to v6 (#2530)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[peter-evans/create-issue-from-file](https://redirect.github.com/peter-evans/create-issue-from-file)
| action | major | `v5` → `v6` |

---

### Release Notes

<details>
<summary>peter-evans/create-issue-from-file
(peter-evans/create-issue-from-file)</summary>

###
[`v6`](https://redirect.github.com/peter-evans/create-issue-from-file/compare/v5...v6)

[Compare
Source](https://redirect.github.com/peter-evans/create-issue-from-file/compare/v5...v6)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

🚦 **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.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/googleapis/genai-toolbox).

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

Author: renovate-bot

.github/workflows/link_checker_report.yaml

@@ -56,7 +56,7 @@ jobs:
 
       - name: Create Issue From File
         if: steps.lychee-check.outcome == 'failure'
-        uses: peter-evans/create-issue-from-file@e8ef132d6df98ed982188e460ebb3b5d4ef3a9cd # v5
+        uses: peter-evans/create-issue-from-file@fca9117c27cdc29c6c4db3b86c48e4115a786710 # v6
         with:
           title: Link Checker Report
           content-filepath: full-report.md