Cleanup test classes

...lin/de/justjanne/libquassel/client/ConnectedClientTest.kt

...est/kotlin/de/justjanne/libquassel/client/DatabaseTest.kt

...otlin/de/justjanne/libquassel/client/OfflineClientTest.kt

...t/kotlin/de/justjanne/libquassel/client/QuasselApiTest.kt

...rc/test/kotlin/de/justjanne/libquassel/di/ClientModule.kt

...in/de/justjanne/libquassel/di/ConnectedClientComponent.kt

...otlin/de/justjanne/libquassel/di/ConnectedClientModule.kt

...t/kotlin/de/justjanne/libquassel/di/ConnectedProxyImpl.kt

.../test/kotlin/de/justjanne/libquassel/di/DatabaseModule.kt

...tlin/de/justjanne/libquassel/di/OfflineClientComponent.kt

.../kotlin/de/justjanne/libquassel/di/OfflineClientModule.kt

...est/kotlin/de/justjanne/libquassel/di/OfflineProxyImpl.kt

...est/kotlin/de/justjanne/libquassel/di/QuasselApiClient.kt