old global settings should be updated instead of reset

[Crackvignoule]

Before commit a63858d, when a global setting (QSetting, stored in OS registry) name were changed in the code it could result in the app not starting cause the setting would no longer exist. For example if the click mode has been renamed from 'fitting' to 'peaks'. Due to this change, line
radio_button = getattr(self.view.toolbar, f"{self.model.click_mode}_radio")
would try to get 'fitting_radio' attr but no longer exists since its now 'peaks_radio', that was causing a crash.

In commit a63858d I implemented a temp fix that detects when fitspy has been updated and proceeds with a settings reset.

Ideally, _check_version would not reset settings but instead update settings keys to keep user settings.