Update Composer installer package to support Composer 2

Author: tfrommen

composer.json

@@ -10,7 +10,7 @@
 		"fig-r/psr2r-sniffer": "^0.5.0",
 		"phpcompatibility/phpcompatibility-wp": "^2.0.0",
 		"squizlabs/php_codesniffer": "~3.5.0",
-		"dealerdirect/phpcodesniffer-composer-installer": "^0.6.0"
+		"dealerdirect/phpcodesniffer-composer-installer": "^0.7.0"
 	},
 	"require-dev": {
 		"phpunit/phpunit": "^5.7"