chore(deps): update sap/project-piper-action action to v1.21.0 (#7513)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[SAP/project-piper-action](https://redirect.github.com/SAP/project-piper-action)
| action | minor | `v1.20.0` -> `v1.21.0` |

---

### Release Notes

<details>
<summary>SAP/project-piper-action (SAP/project-piper-action)</summary>

###
[`v1.21.0`](https://redirect.github.com/SAP/project-piper-action/releases/tag/v1.21.0)

[Compare
Source](https://redirect.github.com/SAP/project-piper-action/compare/v1.20.0...v1.21.0)

##### What's Changed

- feat: pass PIPER\_PIPELINE\_TEMPLATE\_NAME env var to docker container
by [@&#8203;Googlom](https://redirect.github.com/Googlom) in
[https://github.com/SAP/project-piper-action/pull/282](https://redirect.github.com/SAP/project-piper-action/pull/282)

**Full Changelog**:
SAP/project-piper-action@v1.20.0...v1.21.0

</details>

---

### Configuration

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Automerge - At any time (no schedule defined).

🚦 **Automerge**: Enabled.

♻ **Rebasing**: Whenever PR is behind base branch, 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/SAP/ui5-webcomponents-react).

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Author: renovate[bot]

.github/workflows/open-source-security.yml

@@ -16,13 +16,13 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: artifactPrepareVersion
-        uses: SAP/project-piper-action@v1.20.0
+        uses: SAP/project-piper-action@v1.21.0
         with:
           step-name: artifactPrepareVersion
           flags: --versioningType cloud_noTag
 
       - name: detectExecuteScan
-        uses: SAP/project-piper-action@v1.20.0
+        uses: SAP/project-piper-action@v1.21.0
         with:
           step-name: detectExecuteScan
           flags: '--token ${{ secrets.DETECT_TOKEN }}'