vmm: imporve observability to vmm-task & vmm-sandboxer #1251

Job	Run time
tests (vmm/sandbox, --all-features)	3m 18s
tests (vmm/task, --all-features)	2m 57s
checks (vmm/sandbox, --all-features)	1m 43s
tests (shim, --all-features)	2m 33s
tests (quark, --all-features)	2m 34s
checks (vmm/task, --all-features)	1m 46s
tests (runc, --all-features)	3m 1s
checks (shim, --all-features)	1m 47s
tests (wasm, --features=wasmedge, 0.13.5)	3m 14s
checks (quark, --all-features)	1m 46s
tests (wasm, --features=wasmtime)	2m 48s
checks (runc, --all-features)	1m 27s
checks (wasm, --features=wasmedge, 0.13.5)	1m 39s
checks (wasm, --features="wasmedge, wasmedge_wasi_nn", 0.13.5)	1m 42s
checks (wasm, --features=wasmtime)	1m 45s
	34m 0s

Provide feedback