Bump postcss from 8.5.25 to 8.5.26 in the all group (#3137)

Bumps the all group with 1 update: [postcss](https://github.com/postcss/postcss).


Updates `postcss` from 8.5.25 to 8.5.26
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.25...8.5.26)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.26
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: all
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]