Revert hidding warnings in examples

Author: GromNaN

CONTRIBUTING.md

@@ -43,12 +43,6 @@ credentials in the connection string (i.e. `MONGODB_URI`) or set the
 Note that `MONGODB_USERNAME` and `MONGODB_PASSWORD` will override any
 credentials present in the connection string.
 
-To run tests use the `phpunit` executable installed by Composer:
-
-```console
-$ vendor/bin/phpunit
-```
-
 ### Environment Variables
 
 The test suite references the following environment variables:

tests/ExamplesTest.php

@@ -5,15 +5,11 @@
 use Generator;
 
 use function bin2hex;
-use function error_reporting;
 use function getenv;
 use function putenv;
 use function random_bytes;
 use function sprintf;
 
-use const E_ALL;
-use const E_DEPRECATED;
-
 /** @runTestsInSeparateProcesses */
 final class ExamplesTest extends FunctionalTestCase
 {
@@ -308,14 +304,7 @@ public function testWithTransaction(): void
 
     private function assertExampleOutput(string $file, string $expectedOutput): void
     {
-        // Hide deprecation messages
-        $level = error_reporting(E_ALL ^ E_DEPRECATED);
-
-        try {
-            require $file;
-        } finally {
-            error_reporting($level);
-        }
+        require $file;
 
         $this->assertStringMatchesFormat($expectedOutput, $this->getActualOutputForAssertion());
     }