Remove use of user level qmk callbacks

[nskobelevs]

Issue Description

Some of the Bluetooth code defines _user specific qmk callbacks, more specifically:

led_matrix_indicators_user, rgb_matrix_indicators_user and dip_switch_update_user in factory_test.c
and led_matrix_indicators_user and rgb_matrix_indicators_user in indicator.c.

I think there's also a non standard handling of dip_switch_update_user in (among others) q3_pro.c. (I would expect the user callback to be called first before modifying the default layer)

Having these as user level means if someone wants to define their own ones, they'd need to go and modify the existing firmware to avoid multiple definitions.

Is there any reason these need to be at the user level and not at the keyboard level? Could these be renamed and called explicitly from the _kb callbacks?

I'm happy to open up a PR if this is okay to change ^