Do not check framework-provided VK1.3.robustImageAccess feature

Do not check framework-provided VK1.3.robustImageAccess feature

In f7a8ccc2 the value of robustImageAccess  reported and requested by the
framework was forced to be always-FALSE, as it had potential overhead
on some implementations.

However, the extension support check for VK_EXT_image_robustness
extension was still relying on it, so related tests are now unrunnable
 - they always return not supported.

As related tests seem to do own feature checks and custom device creation,
it looks safe to remove checking for feature from extension support check.

VK-GL-CTS Issue: 4241

Components: Vulkan, Framework

Affects:
dEQP-VK.robustness.pipeline_robustness.image_robustness.*
dEQP-VK.robustness.image_robustness.*
dEQP-VK.*

Change-Id: I3f9f9c09ce271a965e2a8625ce010b9efd1abc34