tests: patch localtime in the "cert remainingdays" test

[evverx]

to make sure the code where the invalid timezone is passed to exercise the localtime code path doesn't fail as time goes by.

The other test was added to exercise the code path where the second format is passed.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.30%. Comparing base (2b220b9) to head (144112b).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #4956       +/-   ##
===========================================
+ Coverage   47.61%   80.30%   +32.69%     
===========================================
  Files         361      379       +18     
  Lines       92766    93107      +341     
===========================================
+ Hits        44170    74772    +30602     
+ Misses      48596    18335    -30261     

see 332 files with indirect coverage changes

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[gpotter2]

Yeah, let's merge it asap to unblock downstream.

[gpotter2]

Thanks !