feat(*): Force composer to use PHP 7.2

Author: julienloizelet

composer.json

@@ -8,8 +8,12 @@
 			"email": "info@crowdsec.net"
 		}
 	],
+	"config" : {
+		"platform": {
+			"php": "7.2.34"
+		}
+	},
 	"require": {
-		"php": "^7.2",
 		"crowdsec/bouncer": "0.15.0",
 		"symfony/polyfill-mbstring": "1.20.0",
 		"symfony/service-contracts": "2.4.1"