Add SetAndCheckTenantSetting functional testing utility function

[schrolla]

🗣 Description

Adds a new SetAndCheckTenantSetting to the functional testing utilities available for use in YAML-based testplans. The function supports taking two script blocks: one to change a tenant setting and another to test that the value has changed. If the value has not changed as expected, the set will be retried a user-defined number of times over a specified retry interval.
In addition, both the SharePoint PnP and PowerPlatform test plans have been updated to use the retry functions in tests that have previously been problematic in terms of false positives due to configurations not changing as requested.

💭 Motivation and context

Attempts to resolve issues where a test pre-condition requires changing a tenant setting, but the setting doesn't reliably change or report actual success. The function is meant to ensure that the tenant reflects the requested configuration change prior to running the actual test.

Closes #1364

🧪 Testing

Either run one of the updated test plans or create/modify another testplan to use the function. It does require creating or migrating existing pre-condition commands into the SetBlock and creating a new CheckBlock that retrieves that value and checks its value, returning a boolean result.

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