[ios] Fix incorrect center coordinate after pinch gesture

[astojilj]

To changelogs:
Fixed incorrect center coordinate after pinch regression caused by edge insets fix (#14664).

While working on #14664, missed to understand the logic used in

                CLLocationCoordinate2D centerCoordinate = _previousPinchCenterCoordinate;
                mbgl::EdgeInsets padding { centerPoint.y, centerPoint.x, self.size.height - centerPoint.y, self.size.width - centerPoint.x };
                self.mbglMap.jumpTo(mbgl::CameraOptions()
                                        .withCenter(MGLLatLngFromLocationCoordinate2D(centerCoordinate))
                                        .withPadding(padding));

Replacing this code by moveBy achieves the required translation.

Fixes #14977 and fixes #15082.

[friedbunny]

Thanks for jumping on this, @astojilj — this does indeed fix the rotation issue I was seeing, at the very least. (I haven’t looked wider yet.)

To confirm that this fixes the full range of the reported problems (annotation selection, wrong center coordinate, etc.) are there tests that we can add?

[julianrex]

@friedbunny I have added a changelog for this PR and have tested manually. I added some rotation/selection tests in https://github.com/mapbox/mapbox-gl-native/tree/jrex/rotation-tests, but they do not repro this particular issue. I will try to add another for this.

Can you please review and merge? (or I'll merge given that @astojilj is on vacation).

@astojilj does this same fix need to be added to the macOS's MGLMapView?

[friedbunny]

Regarding tests: MGLMapViewDirectionTests is the basic sort of thing I had in mind, apologies for not linking to that sooner. Annotation selection and such is likely a bit trickier, though...

[friedbunny]

Thanks for fixing this, @astojilj — sorry we didn’t catch it in the original review. 🙇

I’m adding a regression test for this over in #15117.

[astojilj]

@astojilj does this same fix need to be added to the macOS's MGLMapView?

No. Thanks - it is only for iOS.