Composer: Make Dependency Constraint be Less Restrictive

Author: zanbaldwin

Diff for: composer.json

@@ -17,7 +17,7 @@
         "php-http/discovery": "^1.0",
         "psr/http-client-implementation": "^1.0",
         "php-http/client-common": "^1.9 || ^2.0",
-        "php-http/message-factory": "^1.1",
+        "php-http/message-factory": "^1.0",
         "composer-runtime-api": "^2.0"
     },
     "require-dev": {