Bump apollo-client from 2.5.1 to 2.6.3

Bumps [apollo-client](https://github.com/apollographql/apollo-client) from 2.5.1 to 2.6.3.
- [Release notes](https://github.com/apollographql/apollo-client/releases)
- [Changelog](https://github.com/apollographql/apollo-client/blob/master/CHANGELOG.md)
- [Commits](https://github.com/apollographql/apollo-client/compare/apollo-client@2.5.1...apollo-client@2.6.3)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -61,7 +61,7 @@
     "@babel/preset-env": "7.4.5",
     "@parse/minami": "1.0.0",
     "apollo-cache-inmemory": "1.5.1",
-    "apollo-client": "2.5.1",
+    "apollo-client": "2.6.3",
     "apollo-link": "1.2.11",
     "apollo-link-http": "1.5.14",
     "apollo-link-ws": "1.0.17",