fixed website deployment condition logic

Summary:Rookie mistake I made.

**Test plan (required)**

See that https://circleci.com/gh/facebook/react-native/5462 succeeds deploying the website correctly.
Closes https://github.com/facebook/react-native/pull/7063

Differential Revision: D3196198

fb-gh-sync-id: 14fdc94fad0b1e5ff74cc90bb89d2bd1bf29bfa3
fbshipit-source-id: 14fdc94fad0b1e5ff74cc90bb89d2bd1bf29bfa3

website/publish-gh-pages.js

@@ -96,7 +96,7 @@ if (!CI_PULL_REQUEST && CIRCLE_PROJECT_USERNAME === `facebook`) {
   if (currentCommit === latestTagCommit) {
     echo(`------------ DEPLOYING latest`);
     // leave only releases and blog folder
-    rm(`-rf`, ls(`*`).filter(name => (name !== 'releases') || (name !== 'blog')));
+    rm(`-rf`, ls(`*`).filter(name => (name !== 'releases') && (name !== 'blog')));
     cd(`../..`);
     if (exec(`RN_VERSION=${version} RN_LATEST_VERSION=${latestVersion} \
     RN_AVAILABLE_DOCS_VERSIONS=${versions} node server/generate.js`).code !== 0) {