Update secp256k1 dependency #297

Job	Run time
Nightly - ASan + Bench + Docs	1m 3s
Tests (1.56.1, ubuntu-latest)	2m 21s
Tests (beta, ubuntu-latest)	1m 7s
Tests (beta, macos-latest)	1m 22s
Tests (stable, ubuntu-latest)	1m 7s
Tests (stable, macos-latest)	58s
Release tests with global context enabled (1.56.1, ubuntu-latest)	1m 14s
Release tests with global context enabled (beta, ubuntu-latest)	22s
WASM (stable)	48s
Release tests with global context enabled (beta, macos-latest)	28s
WASM (beta)	54s
Release tests with global context enabled (stable, ubuntu-latest)	16s
WASM (nightly)	50s
Release tests with global context enabled (stable, macos-latest)	21s
	13m 11s

Provide feedback