Bump pnpm/action-setup from 3 to 4

Bumps [pnpm/action-setup](https://github.com/pnpm/action-setup) from 3 to 4.
- [Release notes](https://github.com/pnpm/action-setup/releases)
- [Commits](pnpm/action-setup@v3...v4)

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

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

.github/workflows/main.yml

@@ -13,7 +13,7 @@ jobs:
         uses: actions/checkout@v4
 
       # https://github.com/pnpm/action-setup
-      - uses: pnpm/action-setup@v3
+      - uses: pnpm/action-setup@v4
         with:
           version: 6
 

.github/workflows/release.yml

@@ -20,7 +20,7 @@ jobs:
           fetch-depth: 0
 
       # https://github.com/pnpm/action-setup
-      - uses: pnpm/action-setup@v3
+      - uses: pnpm/action-setup@v4
         with:
           version: 6