build: use yarn to run scripts consistently

package.json

@@ -3,16 +3,16 @@
   "description": "Collect end-user data",
   "main": "lib/index.js",
   "scripts": {
-    "build": "npm run build:clean && npm run build:production && npm run build:debug && npm run fileStats",
+    "build": "yarn run build:clean && yarn run build:production && yarn run build:debug && yarn run fileStats",
     "build:clean": "rm -rf target",
-    "build:production": "NODE_ENV=production FILENAME=eum npm run build:bundle",
-    "build:debug": "NODE_ENV=development FILENAME=eum.debug npm run build:bundle",
-    "build:bundle": "npm run build:rollup && npm run build:minify",
+    "build:production": "NODE_ENV=production FILENAME=eum yarn run build:bundle",
+    "build:debug": "NODE_ENV=development FILENAME=eum.debug yarn run build:bundle",
+    "build:bundle": "yarn run build:rollup && yarn run build:minify",
     "build:rollup": "rollup -c -m",
     "build:minify": "google-closure-compiler --compilation_level=ADVANCED --language_in=ECMASCRIPT5_STRICT --language_out=ECMASCRIPT3 --js_output_file=target/$FILENAME.min.js --jscomp_off checkVars --jscomp_off checkTypes --create_source_map='%outname%.map' --formatting=SINGLE_QUOTES target/$FILENAME.js && echo \"//# sourceMappingURL=$FILENAME.min.js.map\" >> target/$FILENAME.min.js && sed -i.bak 's#\"target/#\"#' target/$FILENAME.min.js.map && rm target/$FILENAME.min.js.map.bak",
-    "precommit": "npm run test:quick",
-    "test": "IS_TEST=true npm run test:quick && npm run test:e2e:local",
-    "test:quick": "npm run test:unit && npm run test:lint && npm run test:flow",
+    "precommit": "yarn run test:quick",
+    "test": "IS_TEST=true yarn run test:quick && yarn run test:e2e:local",
+    "test:quick": "yarn run test:unit && yarn run test:lint && yarn run test:flow",
     "test:unit": "jest --coverage --collectCoverageFrom=\"lib/**/*.js\" test/unit/* test/server/*",
     "test:unit:watch": "jest --watch test/unit/* test/server/*",
     "test:e2e:local": "IS_TEST=true protractor protractor.local.config.js",