package.json: Fix unit-nyan script

On test failures, npms error logs distorted the nyan cat rendering

Author: RandomByte

package.json

@@ -23,7 +23,7 @@
 		"unit": "rimraf test/tmp && ava",
 		"unit-verbose": "rimraf test/tmp && cross-env UI5_LOG_LVL=verbose ava --verbose --serial",
 		"unit-watch": "rimraf test/tmp && ava --watch",
-		"unit-nyan": "npm run unit -- --tap | tnyan",
+		"unit-nyan": "rimraf test/tmp && ava --tap | tnyan",
 		"unit-inspect": "cross-env UI5_LOG_LVL=verbose node --inspect-brk node_modules/ava/profile.js",
 		"coverage": "nyc npm run unit",
 		"jsdoc": "npm run jsdoc-generate && opn jsdocs/index.html",