Improve bb-bus caching

[digorath]

Currently the apollo cache is disabled for bb bus details because the id of the service is not unique. (the content depends on area as well).

this could be improved.

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jo, i did some more research.
we can come back to it at some later point: https://www.apollographql.com/docs/react/v2/caching/cache-configuration/#assigning-unique-identifiers

Originally posted by @donni106 in #419 (comment)

[donni106]

++ i found out that there is a

https://github.com/ikuseiGmbH/smart-village-app-app/blob/efdf33b7c9653eee062d3c1161f6e5f4793ccb1a/src/hooks/apollo.ts#L10-L12

but we do not use it. instead we do

https://github.com/ikuseiGmbH/smart-village-app-app/blob/efdf33b7c9653eee062d3c1161f6e5f4793ccb1a/src/screens/BB-BUS/DetailScreen.js#L108-L113