Bump ramsey/composer-install from 2 to 3

Bumps [ramsey/composer-install](https://github.com/ramsey/composer-install) from 2 to 3.
- [Release notes](https://github.com/ramsey/composer-install/releases)
- [Commits](ramsey/composer-install@v2...v3)

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

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

.github/workflows/continuous-integration.yml

@@ -36,7 +36,7 @@ jobs:
           coverage: none
 
       - name: "Install dependencies (Composer)"
-        uses: "ramsey/composer-install@v2"
+        uses: "ramsey/composer-install@v3"
 
       - name: "Check coding standards (PHP CS Fixer)"
         shell: "bash"
@@ -56,7 +56,7 @@ jobs:
           coverage: "none"
 
       - name: "Install dependencies (Composer)"
-        uses: "ramsey/composer-install@v2"
+        uses: "ramsey/composer-install@v3"
 
       - name: "Statically analyze code (PHPStan)"
         shell: "bash"
@@ -76,7 +76,7 @@ jobs:
           ini-values: "memory_limit=-1"
 
       - name: "Install dependencies (Composer)"
-        uses: "ramsey/composer-install@v2"
+        uses: "ramsey/composer-install@v3"
 
       - name: "Run unit tests (PHPUnit)"
         shell: "bash"