[Vulkan][KosmicKrisp] GroupMemoryBarrierWithGroupSync fails to create pipeline

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Offloader is failing on GroupMemoryBarrierWithGroupSync.test. There is not enough information in the output to know why. This test is passing on DXC for this same test.

```
Using Vulkan API
Physical device created.
Shader module created.
Copy command buffer created.
Memory buffers created.
Executed copy command buffer.
Execute command buffer created.
Descriptors: { type = 7, count = 1 }
Descriptor pool created.
Binding 1 descriptors.
Num Descriptor sets: 1
Updating Descriptor [0] { 0, 0 }
WriteDescriptors: 1
Descriptor sets created.
gpu-exec: error: Failed to create pipeline.
```

Start with GroupMemoryBarrierWithGroupSync.test and reproduce the failure through gpu-exec using the Vulkan path. Compare the Vulkan and DXC results, then trace the pipeline-creation failure until the output identifies its cause and the test creates a pipeline successfully.

Written by the indexing model from the issue text.