Improve UIA movement testing methodology (#10886)

Introduces a new methodology to maintain tests for UI Automation. This includes...
- `UiaTests.csv`: an excel spreadsheet designed to store UIA movement tests in a compact format
- `GeneratedTests.ps1`: a PowerShell script that imports `UiaTests.csv` and outputs a C++ TEST_METHOD for `UiaTextRangeTests.

This new system can be used to easily add more UIA movement tests.

Read https://github.com/microsoft/terminal/blob/dev/cazamor/a11y-7000/testing/tools/TestTableWriter/README.md for more details.

Follow-up work items:
- #10924 **Failing Tests**: this found some failing tests. We should make them not fail.
- #10925 **Missing Tests: Word navigation**: Word navigation is missing.
- #10926 **MoveEndpoint Tests**: an additional column can be added to the CSV "EndpointTarget", which can be "start", "end", or "both". This will allow us to test `MoveEndpoint` in addition to `Move`.

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@@ -50,6 +51,7 @@ timestamped
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