fix(config): Workaround npm 5.4 windows bug

johnjbarton · zzo · commit ec47d8115e48 · 2017-11-15T11:16:17.000-08:00
See npm/npm#18380
diff --git a/appveyor.yml b/appveyor.yml
@@ -16,7 +16,7 @@ install:
   - ps: Install-Product node $env:nodejs_version
 
   # Upgrade npm
-  - npm install -g npm
+  - npm install -g npm@5.3
 
   # Output our current versions for debugging
   - node --version
