Structure_Engine: Update `PileFoundation` Geometry method

[peterjamesnugent]

Issues addressed by this PR

Closes #3411

Test files

https://burohappold.sharepoint.com/:u:/s/BHoM/EYbRjWNJQ3xDnepsnRTz1cQBaOOADL2wUdPn9FdauQ_ZOw?e=MqaFkK

Changelog

• Updated PileFoundation Geometry method to use IRegion Geometry method for the PileCap.

Additional comments

[peterjamesnugent]

@BHoMBot check required

[bhombot-ci[bot]]

@peterjamesnugent to confirm, the following actions are now queued: - check `code-compliance` - check `documentation-compliance` - check `project-compliance` - check `core` - check `null-handling` - check `serialisation` - check `versioning` - check `installer`

[peterjamesnugent]

@BHoMBot check copyright-compliance @BHoMBot check dataset-compliance @BHoMBot check unit-tests

[bhombot-ci[bot]]

@peterjamesnugent to confirm, the following actions are now queued: - check `copyright-compliance` - check `dataset-compliance` - check `unit-tests`

[peterjamesnugent]

@BHoMBot check ready-to-merge

[bhombot-ci[bot]]

@peterjamesnugent to confirm, the following actions are now queued: - check `ready-to-merge`