Test non-filterable textures can't be used with filtering sampler.

[greggman]

IIUC these tests are missing from the CTS

Note that if u32/i32 are removed from textureGather then there is no other texture builtin that uses u32/i32 except textureLoad

Testing locally on Chrome with this patch check does this validation they pass.
With this patch that does this validation but allows depth with a deprecation warning they all pass except for depth. On Chrome Canary with neither patch they all fail except for the f32 tests which are supposed to work.

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Requirements for PR author:

• All missing test coverage is tracked with "TODO" or .unimplemented().
• New helpers are /** documented */ and new helper files are found in helper_index.txt.
• Test behaves as expected in a WebGPU implementation. (If not passing, explain above.)
• Test have be tested with compatibility mode validation enabled and behave as expected. (If not passing, explain above.)

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• Tests are properly located in the test tree.
• Test descriptions allow a reader to "read only the test plans and evaluate coverage completeness", and accurately reflect the test code.
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