Fixed the syntax of the "coverage" script

Author: JamesMessinger

package.json

@@ -39,7 +39,7 @@
     "build:node_modules": "shx mkdir -p dist/node_modules && shx cp -r node_modules/semver dist/node_modules",
     "watch": "tsc --watch",
     "test": "mocha && npm run lint",
-    "coverage": "nyc -x test/** -x dist/sourcemap-register.js node_modules/mocha/bin/mocha",
+    "coverage": "nyc -x test -x dist/sourcemap-register.js node_modules/mocha/bin/mocha",
     "upgrade": "npm-check -u && npm audit fix",
     "bump": "bump --tag --push --all && git tag -afm v1 v1 && git push --tags --force",
     "release": "npm run upgrade && npm run clean && npm run build && npm test && npm run bump"