chore: Remove `msg_type` method from `MsgVariant` #1302

Job	Run time
Commits consistency	2s
macOS	6m 30s
Test UI (macOS, macOS-latest)	4m 6s
Code coverage	6m 32s
Windows	18m 17s
Test UI (Windows, windows-latest)	7m 6s
	42m 33s

Provide feedback