Fix WebGPU Conv auto_pad=SAME_UPPER padding calculation #8554

Job	Run time
4. Build Minimal (Globally Allowed Types)	1d 0h 9m 42s
6c. Build Extended Minimal (No Optional Features)	1s
5. Build Extended Minimal	1s
1. Build Full ORT and Generate ORT Files	1s
6b. Build Minimal (No Optional Features)	1s
2. Build Minimal (Exceptions Disabled)	1s
6a. Build Regular (No Optional Features)	1s
3a. Build Minimal (Custom Ops)	0s
3b. Build Minimal (Type Reduction)	0s
7. Build Extended Minimal (Android NNAPI)	0s
1. Build Full ORT and Generate ORT Files	17m 6s
6a. Build Regular (No Optional Features)	12m 18s
4. Build Minimal (Globally Allowed Types)	8m 21s
6b. Build Minimal (No Optional Features)	7m 27s
2. Build Minimal (Exceptions Disabled)	10m 16s
5. Build Extended Minimal	10m 34s
6c. Build Extended Minimal (No Optional Features)	7m 49s
3a. Build Minimal (Custom Ops)	8m 53s
3b. Build Minimal (Type Reduction)	8m 40s
7. Build Extended Minimal (Android NNAPI)	10m 6s
	1d 1h 51m 18s

Provide feedback