dynamic_rendering_local_read needs to turn off color write mask on 2nd/3rd draw

[spencer-lunarg]

With the Latest ToT Validation the dynamic_rendering_local_read example gives the following

Validation Warning: [ Undefined-Value-ShaderInputNotProduced-DynamicRendering ] | MessageID = 0x733b5ff8
vkCmdDrawIndexed(): Inside the fragment shader, the output Locaiton 1 was never written to. This means the bound VkRenderingInfo::pColorAttachments[1].imageView (VkImageView 0x3a6cbb0000000025) will have undefined values written to it.The pipeline was created with pColorBlendState->pAttachments[1].colorWriteMask 0xf so setting it to zero is one way to prevent undefined values overriding your color attachment.
Spec information at https://docs.vulkan.org/spec/latest/chapters/interfaces.html#interfaces-fragmentoutput
Objects: 2
    [0] VkCommandBuffer 0x59c2af1c3320
    [1] VkPipeline 0xc25f26000000009c

Simple fix is to

1. enable independentBlend (basically supported everywhere)
2. adjust the blend_attachment_states for the 2 pipelines not writing out to the color attachments