BackendService has leaked IntentReceiver and Receiver not registered: org.microg.nlp.api.WiFiBackendHelper

Nobody has claimed this yet.

**Describe the bug**
I just get the crash without doing nothing special.

**System**
Android Version: 7
Custom ROM: LineageOS 14.1

**microG**
microG Core version: 0.2.24.214816
IchnaeaNlpBackend version: 1.5.0
microG Self-Check results: All ticked

**Additional context**
```
[ 05-08 19:18:14.698 3488: 3488 E/ActivityThread ]
Service org.microg.nlp.backend.ichnaea.BackendService has leaked IntentReceiver org.microg.nlp.api.WiFiBackendHelper$1@ba2a62d that was originally registered here. Are you missing a call to unregisterReceiver()?
android.app.IntentReceiverLeaked: Service org.microg.nlp.backend.ichnaea.BackendService has leaked IntentReceiver org.microg.nlp.api.WiFiBackendHelper$1@ba2a62d that was originally registered here. Are you missing a call to unregisterReceiver()?
at android.app.LoadedApk$ReceiverDispatcher.(LoadedApk.java:1159)
at android.app.LoadedApk.getReceiverDispatcher(LoadedApk.java:946)
at android.app.ContextImpl.registerReceiverInternal(ContextImpl.java:1302)
at android.app.ContextImpl.registerReceiver(ContextImpl.java:1282)
at android.app.ContextImpl.registerReceiver(ContextImpl.java:1276)
at android.content.ContextWrapper.registerReceiver(ContextWrapper.java:586)
at org.microg.nlp.api.WiFiBackendHelper.onOpen(WiFiBackendHelper.java:80)
at org.microg.nlp.api.HelperLocationBackendService.addHelper(HelperLocationBackendService.java:33)
at org.microg.nlp.backend.ichnaea.BackendService.reloadSettings(BackendService.java:139)
at org.microg.nlp.backend.ichnaea.BackendService.onOpen(BackendService.java:110)
at org.microg.nlp.api.LocationBackendService$Backend.open(LocationBackendService.java:88)
at org.microg.nlp.api.LocationBackend$Stub.onTransact(LocationBackend.java:84)
at android.os.Binder.execTransact(Binder.java:565)

[ 05-08 19:18:14.716 2364: 2964 W/ActivityManager ]
Scheduling restart of crashed service com.google.android.gms/org.microg.nlp.location.v3.LocationService in 1000ms

[ 05-08 19:18:14.716 2364: 2964 W/ActivityManager ]
Scheduling restart of crashed service com.google.android.gms/org.microg.nlp.geocode.v1.GeocodeService in 10995ms

[ 05-08 19:18:14.717 2364: 2964 W/ActivityManager ]
Scheduling restart of crashed service com.google.android.gms/.analytics.service.AnalyticsService in 20995ms
```

```
[ 05-08 19:20:22.831 2364: 9142 I/ActivityManager ]
START u0 {act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10200000 cmp=com.android.messaging/.ui.conversationlist.ConversationListActivity bnds=[20,695][108,800] (has extras)} from uid 10029 on display 0

[ 05-08 19:20:22.931 2364: 2519 I/ActivityManager ]
Start proc 9456:com.android.messaging/u0a67 for activity com.android.messaging/.ui.conversationlist.ConversationListActivity

[ 05-08 19:20:23.604 3488: 3488 E/AndroidRuntime ]
FATAL EXCEPTION: main
Process: org.microg.nlp.backend.ichnaea, PID: 3488
java.lang.RuntimeException: Unable to create service org.microg.nlp.backend.ichnaea.BackendService: java.lang.IllegalArgumentException: Receiver not registered: org.microg.nlp.api.WiFiBackendHelper$1@ba2a62d
at android.app.ActivityThread.handleCreateService(ActivityThread.java:3226)
at android.app.ActivityThread.-wrap5(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1586)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6186)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:889)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)
Caused by: java.lang.IllegalArgumentException: Receiver not registered: org.microg.nlp.api.WiFiBackendHelper$1@ba2a62d
at android.app.LoadedApk.forgetReceiverDispatcher(LoadedApk.java:1007)
at android.app.ContextImpl.unregisterReceiver(ContextImpl.java:1330)
at android.content.ContextWrapper.unregisterReceiver(ContextWrapper.java:608)
at org.microg.nlp.api.WiFiBackendHelper.onClose(WiFiBackendHelper.java:88)
at org.microg.nlp.api.HelperLocationBackendService.removeHelpers(HelperLocationBackendService.java:40)
at org.microg.nlp.backend.ichnaea.BackendService.reloadSettings(BackendService.java:126)
at org.microg.nlp.backend.ichnaea.BackendService.reloadInstanceSettings(BackendService.java:118)
at org.microg.nlp.backend.ichnaea.BackendService.onCreate(BackendService.java:61)
at android.app.ActivityThread.handleCreateService(ActivityThread.java:3216)
... 8 more

[ 05-08 19:20:23.654 2364: 9481 W/DropBoxManagerService ]
Dropping: system_app_crash (1864 > 0 bytes)

[ 05-08 19:20:23.670 2364: 2375 D/MmsServiceBroker ]
getCarrierConfigValues() by com.android.messaging

[ 05-08 19:20:24.082 2364: 7794 D/MmsServiceBroker ]
getCarrierConfigValues() by com.android.messaging

[ 05-08 19:20:25.928 2364: 2376 D/MmsServiceBroker ]
getCarrierConfigValues() by com.android.messaging

[ 05-08 19:20:33.717 2364: 2519 I/ActivityManager ]
Killing 3488:org.microg.nlp.backend.ichnaea/u0a65 (adj 0): crash

[ 05-08 19:20:33.717 2364: 2519 D/ActivityManager ]
cleanUpApplicationRecord -- 3488
```

Start with org.microg.nlp.api.WiFiBackendHelper, especially onOpen and onClose, then follow the lifecycle through HelperLocationBackendService and BackendService.reloadSettings. Reproduce the service reload path described in the Android 7 logs and verify that receiver cleanup no longer reports a leaked or unregistered Receiver.

Written by the indexing model from the issue text.