Add test script to composer.json

This makes it easier to run the test script directly from the editor it
your editor supports composer. Otherwise run it from the command line:

    composer run test

Or like before:

    ./run-tests

1 files changed, 3 insertions, 0 deletions

diff --git a/composer.json b/composer.json
index 3b74061..fb612a3 100644
--- a/composer.json
+++ b/composer.json
@@ -15,5 +15,8 @@
     ],
     "require-dev": {
         "wp-phpunit/wp-phpunit": "^5.7"
+    },
+    "scripts": {
+        "test": "./run-tests"
     }
 }