Changing killswitch flags

[kneeyo1]

This removes the automator_modifiable flag from the killswitch options we have.

Leaving it blank has these options pick up the default flag here.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 84.25%. Comparing base (3c45415) to head (34a67f9). Report is 1016 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #64930      +/-   ##
==========================================
- Coverage   84.25%   84.25%   -0.01%     
==========================================
  Files        5293     5293              
  Lines      236792   236792              
  Branches    41007    41007              
==========================================
- Hits       199513   199511       -2     
- Misses      37060    37062       +2     
  Partials      219      219              

Files	Coverage Δ
src/sentry/options/defaults.py	100.00% <100.00%> (ø)

... and 6 files with indirect coverage changes

[getsantry[bot]]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you remove the label Waiting for: Community, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[kneeyo1]

We will be supporting killswitches in the future, closing this PR