[BUGFIX] Respect automaticInstallation setting in extension manager

Prevent the automatic installation of new extensions if the setting
was disabled.

Resolves: #84125
Releases: master, 8.7, 7.6
Change-Id: Ic554e8870543b2f15079f7adfb1ddc2517bfc2b5
Reviewed-on: https://review.typo3.org/56097
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Tobi Kretschmann <tobi@tobishome.de>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>

typo3/sysext/extensionmanager/Classes/Service/ExtensionManagementService.php

@@ -222,7 +222,10 @@ public function installExtension(Extension $extension)
         // Attach extension to install queue
         $this->downloadQueue->addExtensionToInstallQueue($extension);
         $installQueue += $this->downloadQueue->resetExtensionInstallStorage();
-        $installedDependencies = $this->installDependencies($installQueue);
+        $installedDependencies = [];
+        if ($this->automaticInstallationEnabled) {
+            $installedDependencies = $this->installDependencies($installQueue);
+        }
 
         return array_merge($downloadedDependencies, $updatedDependencies, $installedDependencies);
     }