Make TOTP enable/disable views mobile friendly

[Ninjaclasher]

The views were practically unusable on mobile before without forcing desktop mode.

Before (on a small width screen):

Note: you cannot scroll to the left in either of the views.

After:

The views on a larger screen are almost identical. The only changes are that the form is now properly centred and this:
Before:

After:

Note that in the after screenshot, the text still wraps at 700px (not sure why it wraps early in the before screenshot).

[codecov-commenter]

Codecov Report

Merging #1714 (5435536) into master (36ea904) will increase coverage by 0.03%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #1714      +/-   ##
==========================================
+ Coverage   46.38%   46.41%   +0.03%     
==========================================
  Files         217      217              
  Lines       12386    12400      +14     
==========================================
+ Hits         5745     5756      +11     
- Misses       6641     6644       +3     

Impacted Files	Coverage Δ
judge/views/two_factor.py	39.75% <ø> (+0.70%)	⬆️
judge/signals.py	64.19% <20.00%> (-2.91%)	⬇️
judge/models/profile.py	91.27% <80.00%> (-0.34%)	⬇️
judge/admin/profile.py	62.22% <87.50%> (+1.98%)	⬆️

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