webnn: add float32 tests for lstm and lstmCell operators
This CL is to add some float32 conformance tests for lstm and lstmCell
operators based from existed lstm tests of ONNX CTS.
Bug: 356298362
Change-Id: I187db5dba7a794dac47ca2033fefb4a98a036542
Cq-Include-Trybots: luci.chromium.try:win11-blink-rel,mac14-blink-rel,mac14.arm64-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5763402
Reviewed-by: Austin Sullivan asully@chromium.org
Auto-Submit: Feng Dai feng.dai@intel.com
Commit-Queue: David Baron dbaron@chromium.org
Reviewed-by: David Baron dbaron@chromium.org
Cr-Commit-Position: refs/heads/main@{#1341623}