Sort composer dev requirements alphabetically

Author: ericpoe

composer.json

@@ -22,8 +22,8 @@
         "jakub-onderka/php-parallel-lint": "^1.0",
         "phpunit/phpunit": "^5.7",
         "roave/security-advisories": "dev-master",
-        "squizlabs/php_codesniffer": "^3.4",
-        "sensiolabs/security-checker": "^5.0"
+        "sensiolabs/security-checker": "^5.0",
+        "squizlabs/php_codesniffer": "^3.4"
     },
     "autoload" : {
         "psr-4" : {