Log Message:
tex-beamertheme-focus: update to 3.3.0

3.3.0:
Use Fira font also for math.

3.2.0
Fix frame numbering on frames when both `noframenumbering` and
`allowframebreaks` options are used.

3.0.0
Added [totalframenumbering={yes,no}] option to toggle showing the total
frame number.