Fail on extension / tool installation failure

This leverages a new feature of shivammathur/setup-php that allows to
fail the build if an extension or tool fails to install.

Author: greg0ire

.github/workflows/continuous-integration.yml

@@ -13,6 +13,9 @@ on:
   schedule:
     - cron: "42 3 * * *"
 
+env:
+  fail-fast: true
+
 jobs:
   phpunit-smoke-check:
     name: "PHPUnit with SQLite"
@@ -92,7 +95,7 @@ jobs:
         uses: "shivammathur/setup-php@v2"
         with:
           php-version: "${{ matrix.php-version }}"
-          extensions: "oci8"
+          extensions: "does_not_exist"
           coverage: "pcov"
           ini-values: "zend.assertions=1"