Simplify implementation of Dispatch-async bridge #163

Job	Run time
cmake-smoke-test / Linux (nightly-main - noble)	5m 20s
cmake-smoke-test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Test / Linux (nightly-main - noble)	12m 29s
Test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Test / Windows (nightly-main - windows-2019)	1h 8m 30s
Test / Linux (nightly-main - jammy)	12m 2s
Test / Linux (nightly-main - focal)	11m 46s
Test / Linux (nightly-main - rhel-ubi9)	11m 53s
Test / Linux (nightly-6.2 - noble)	11m 52s
Test / Linux (nightly-6.2 - jammy)	12m 5s
Test / Linux (nightly-6.2 - focal)	12m 15s
Test / Linux (nightly-6.2 - rhel-ubi9)	12m 29s
Soundness / API breakage check	0s
Soundness / Broken symlinks check	2s
Soundness / Documentation check	37s
Soundness / Format check	0s
Soundness / License headers check	15s
Soundness / Unacceptable language check	5s
Soundness / Python lint check	7s
Soundness / Shell check	30s
Soundness / YAML lint check	4s
	2h 52m 21s

Provide feedback