fix(nuxt-bridge): add support for nuxt bridge

Nuxt Bridge exposes the Nuxt 2 context via nuxtApp.nuxt2Context.

However, when doing `app.apolloProvider`, the apolloProvider is not added to this context.

In order to get the apolloProvider onto this nuxt2Context, we must use inject().

However, it requires a different name than "apolloProvider" when injecting, or we get errors.

lib/templates/plugin.js

@@ -113,6 +113,7 @@ export default (ctx, inject) => {
   const apolloProvider = new VueApollo(vueApolloOptions)
   // Allow access to the provider in the context
   app.apolloProvider = apolloProvider
+  inject('theApolloProvider', apolloProvider);
 
   if (process.server) {
     const ApolloSSR = require('vue-apollo/ssr')