Remove obsolete branch alias, remove @dev constraints on assets and asset-admin

composer.json

@@ -11,17 +11,15 @@
         "silverstripe/cms": "^4.0",
         "silverstripe/lumberjack": "^2.0",
         "silverstripe/tagfield": "^2.0",
-        "silverstripe/assets": "^1.0@dev",
-        "silverstripe/asset-admin": "^1.0@dev"
+        "silverstripe/assets": "^1.0",
+        "silverstripe/asset-admin": "^1.0"
     },
     "require-dev": {
         "phpunit/PHPUnit": "^5.7",
-        "squizlabs/php_codesniffer": "*"
+        "squizlabs/php_codesniffer": "^3.0"
     },
     "extra": {
-        "branch-alias": {
-            "dev-master": "3.0.x-dev"
-        },
+        "branch-alias": [],
         "expose": [
             "client/dist",
             "client/images"