Bump pypa/gh-action-pypi-publish from 1.5.0 to 1.8.1

Bumps [pypa/gh-action-pypi-publish](https://github.com/pypa/gh-action-pypi-publish) from 1.5.0 to 1.8.1.
- [Release notes](https://github.com/pypa/gh-action-pypi-publish/releases)
- [Commits](pypa/gh-action-pypi-publish@v1.5.0...v1.8.1)

---
updated-dependencies:
- dependency-name: pypa/gh-action-pypi-publish
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/nightly.yml

@@ -23,7 +23,7 @@ jobs:
         run: python -m build --sdist .
         env:
           BUILD_PYTENSOR_NIGHTLY: true
-      - uses: pypa/gh-action-pypi-publish@v1.6.4
+      - uses: pypa/gh-action-pypi-publish@v1.8.1
         with:
           user: __token__
           password: ${{ secrets.nightly_pypi_secret }}

.github/workflows/pypi.yml

@@ -87,7 +87,7 @@ jobs:
         name: artifact
         path: dist
 
-    - uses: pypa/gh-action-pypi-publish@v1.5.0
+    - uses: pypa/gh-action-pypi-publish@v1.8.1
       with:
         user: __token__
         password: ${{ secrets.pypi_password }}