Update cypress/included Docker tag to v12.6.0

This MR contains the following updates:

Package	Type	Update	Change
cypress/included	ironbank-docker	minor	12.5.1 -> 12.6.0
cypress/included		minor	12.5.1 -> 12.6.0
cypress/included	stage	minor	12.5.1 -> 12.6.0

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