Fix MAGN-5376 Element.Geometry not working after reopening file.

Summary

I am regenerating the document before attempting to get geometries from elements. This will fix the defect. But because the test cases are running without starting a transaction, I am modifying the test framework to start a transaction in the setup method.

I am removing one call to ForceCloseTransaction in DocumentManager.Regenerate because it will be duplicated with the one call in RevitDynamoModel.OnEvaluationCompleted.

@pboyer
PTAL

This pull request is created based on the following pull request because of restructure:
https://github.com/DynamoDS/Dynamo/pull/3360