chore(deps): bump pnpm/action-setup from 4 to 6

Bumps [pnpm/action-setup](https://github.com/pnpm/action-setup) from 4 to 6.
- [Release notes](https://github.com/pnpm/action-setup/releases)
- [Commits](pnpm/action-setup@v4...v6)

---
updated-dependencies:
- dependency-name: pnpm/action-setup
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-      - uses: pnpm/action-setup@v4
+      - uses: pnpm/action-setup@v6
       - uses: actions/setup-node@v4
         with:
           node-version: 22
@@ -34,7 +34,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-      - uses: pnpm/action-setup@v4
+      - uses: pnpm/action-setup@v6
       - uses: actions/setup-node@v4
         with:
           node-version: 22
@@ -46,7 +46,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-      - uses: pnpm/action-setup@v4
+      - uses: pnpm/action-setup@v6
       - uses: actions/setup-node@v4
         with:
           node-version: 22