Add AdamW optimizer to extension/training #2324

Job	Run time
test-arm / test-backend-linux (arm_vgf_fp, models) / linux-job	26m 27s
test-arm / test-backend-linux (arm_vgf_fp, operators) / linux-job	17m 8s
test-arm / test-backend-linux (arm_tosa_fp, operators) / linux-job	20m 50s
test-arm / test-backend-linux (arm_tosa_fp, models) / linux-job	25m 36s
test-arm / test-backend-macos	0s
test-arm / package-golden-artifacts	44s
	1h 30m 45s

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