add cron job to nightly tests (#7128)

[IanMatthewHuff]

Port of this PR to release:
#7128

The AzDO pipeline schedules added via the UI have been deprecated. I made a change in master to add in a cron job to do the nightly build. However since this yaml change is only in master branch it only applies to master branch so right now only master branch is getting built on schedule. Pulling in this change will get release on the schedule as well. I've just been building release manually for the last day or two to work around this.

• Pull request represents a single change (i.e. not fixing disparate/unrelated things in a single PR)
• Title summarizes what is changing
• Has a news entry file (remember to thank yourself!)
• Appropriate comments and documentation strings in the code
• Has sufficient logging.
• Has telemetry for enhancements.
• Unit tests & system/integration tests are added/updated
• Test plan is updated as appropriate
• package-lock.json has been regenerated by running npm install (if dependencies have changed)
• The wiki is updated with any design decisions/details.

[kimadeline]

🍒 ⛏

[codecov-io]

Codecov Report

Merging #7158 into release will decrease coverage by 0.05%.
The diff coverage is n/a.

@@ Coverage Diff @@ ## release #7158 +/- ## =========================================== - Coverage 58.48% 58.43% -0.06%  =========================================== Files 485 485 Lines 21437 21437 Branches 3462 3462 =========================================== - Hits 12537 12526 -11  - Misses 8122 8135 +13  + Partials 778 776 -2

Impacted Files	Coverage Δ
src/client/common/logger.ts	68.55% <0%> (-6.92%)	⬇️

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