onnxruntime

bbd27396 - [webgpu] move comments out from WGSL in FlashAttention impl (#24400)

[webgpu] move comments out from WGSL in FlashAttention impl (#24400) ### Description There are 2 benefits to this change: - the comments contain "Σ", a unicode char causing `std::wclog` failed and no longer output future logs on Windows native app, if not enabled UTF-8 explicitly by `std::wclog.imbue(std::locale(".UTF-8"));`. Moving it out resolves the problem. - makes the WGSL code slightly shorter.