Allow composer/installers plugin

`composer update --no-interactive` errors out if this flag is not set.
Setting it to true, as that was the status quo before Composer 2.2.

Bug: T298283
Change-Id: I9805e130a0fd8f9871693a08eec9a35194f19e4e

composer.json

@@ -54,5 +54,10 @@
 		"test:size": "phpunit -c ../../phpunit.xml.dist tests/phpunit/structure/BundleSizeTest.php --verbose",
 		"phan": "phan -d . --long-progress-bar",
 		"phpcs": "phpcs -sp --cache"
+	},
+	"config": {
+		"allow-plugins": {
+			"composer/installers": true
+		}
 	}
 }