chore: do not double build prs

Author: achingbrain

.travis.yml

@@ -1,5 +1,11 @@
 language: node_js
 cache: npm
+
+branches:
+  only:
+  - master
+  - /^release\/.*$/
+
 stages:
   - check
   - test
@@ -57,7 +63,7 @@ jobs:
     - stage: release
       name: release rc
       script:
-        - echo "//registry.npmjs.org/:_authToken=$NPM_TOKEN" > ../.npmrc
+        - echo "//registry.npmjs.org/:_authToken=$NPM_TOKEN" > .npmrc
         - npm whoami
         - npm run release:rc -- --yes