Merge branch '5.0' into 5.1

* 5.0:
  Parse and render anonymous classes correctly on php 8
  Enable APCu for the php 8 build.
  [Process] Fix failing test on php 8.
  [HttpKernel] fix test
  Make PHP 8 green on Travis
  Revert "[Cache] allow DBAL v3"
  [PropertyAccessor] Added missing property path on php 8.
  Don't execute tests with DBAL 2.x on php 8.

Author: nicolas-grekas

Tests/ProcessTest.php

@@ -988,21 +988,20 @@ public function provideMethodsThatNeedATerminatedProcess()
 
     public function testWrongSignal()
     {
-        $this->expectException('Symfony\Component\Process\Exception\RuntimeException');
         if ('\\' === \DIRECTORY_SEPARATOR) {
             $this->markTestSkipped('POSIX signals do not work on Windows');
         }
 
+        $this->expectException(RuntimeException::class);
+
         $process = $this->getProcessForCode('sleep(38);');
         $process->start();
         try {
             $process->signal(-4);
             $this->fail('A RuntimeException must have been thrown');
-        } catch (RuntimeException $e) {
+        } finally {
             $process->stop(0);
         }
-
-        throw $e;
     }
 
     public function testDisableOutputDisablesTheOutput()