Bump ramsey/composer-install from 3 to 4 (#175)

Bumps [ramsey/composer-install](https://github.com/ramsey/composer-install) from 3 to 4.
- [Release notes](https://github.com/ramsey/composer-install/releases)
- [Commits](ramsey/composer-install@v3...v4)

---
updated-dependencies:
- dependency-name: ramsey/composer-install
  dependency-version: '4'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/continuous-integration.yml

@@ -45,7 +45,7 @@ jobs:
       - name: "Remove PHPStan as it requires a newer PHP"
         run: composer remove phpstan/phpstan --dev --no-update
 
-      - uses: ramsey/composer-install@v3
+      - uses: ramsey/composer-install@v4
         with:
           dependency-versions: highest
 

.github/workflows/phpstan.yml

@@ -29,7 +29,7 @@ jobs:
           php-version: "${{ matrix.php-version }}"
           coverage: none
 
-      - uses: ramsey/composer-install@v3
+      - uses: ramsey/composer-install@v4
         with:
           dependency-versions: highest