[DPE-5622] Run tests against juju 3.6/candidate on nightly schedule

[shayancanonical]

Issue

We are not running tests on juju 3.6/*

Solution

Run tests against juju 3.6/candidate on a nightly schedule

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.64%. Comparing base (e99a336) to head (9c0b426).
Report is 8 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #452   +/-   ##
=======================================
  Coverage   71.64%   71.64%           
=======================================
  Files           9        9           
  Lines        1319     1319           
  Branches      217      217           
=======================================
  Hits          945      945           
  Misses        292      292           
  Partials       82       82           

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