Xiaomi: Disable activity fetching outside of Mi Band 8

It has a lot of issues, and should not be enabled to proceed with a
release.

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/xiaomi/XiaomiCoordinator.java

@@ -217,18 +217,20 @@ public abstract class XiaomiCoordinator extends AbstractBLEDeviceCoordinator {
 
     @Override
     public boolean supportsActivityDataFetching() {
-        return true;
+        // TODO It does, but not yet fully working - only in Mi Band 8
+        return false;
     }
 
     @Override
     public boolean supportsActivityTracking() {
-        return true;
+        // TODO It does, but not yet fully working - only in Mi Band 8
+        return false;
     }
 
     @Override
     public boolean supportsActivityTracks() {
         // TODO It does, but not yet fully working
-        return BuildConfig.DEBUG;
+        return false;
     }
 
     @Override

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/xiaomi/miband8/MiBand8Coordinator.java

@@ -61,6 +61,18 @@ public class MiBand8Coordinator extends XiaomiCoordinator {
         return R.drawable.ic_device_miband6_disabled;
     }
 
+    @Override
+    public boolean supportsActivityDataFetching() {
+        // FIXME still has some issues
+        return true;
+    }
+
+    @Override
+    public boolean supportsActivityTracking() {
+        // FIXME still has some issues
+        return true;
+    }
+
     @Override
     public boolean supportsMultipleWeatherLocations() {
         return true;