wgpu_core: Add logging to Instance::new. #7636

Job	Run time
Run `cargo deny check advisories`	3m 54s
Clippy Windows x86_64	3m 8s
Clippy MacOS x86_64	3m 36s
Clippy MacOS aarch64	3m 30s
Clippy IOS aarch64	3m 15s
Clippy Linux x86_64	1m 54s
Clippy Linux aarch64	2m 33s
Clippy Android aarch64	1m 58s
Clippy WebAssembly	1m 45s
Clippy Emscripten	57s
Clippy cts_runner	50s
Run `cargo deny check`	3m 56s
Doctest	1m 13s
Format	25s
Test Windows x86_64	10m 49s
Test Mac aarch64	1m 35s
Test Linux x86_64	6m 39s
Test WebAssembly	6m 4s
	58m 1s

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