vmm: imporve observability to vmm-task & vmm-sandboxer #1258

Job	Run time
tests (vmm/sandbox, --all-features)	4m 0s
checks (vmm/sandbox, --all-features)	5m 11s
tests (vmm/task, --all-features)	3m 3s
checks (vmm/task, --all-features)	4m 18s
tests (shim, --all-features)	2m 30s
checks (shim, --all-features)	3m 55s
tests (quark, --all-features)	2m 28s
checks (quark, --all-features)	3m 58s
tests (runc, --all-features)	3m 2s
checks (runc, --all-features)	4m 32s
tests (wasm, --features=wasmedge, 0.13.5)	3m 26s
checks (wasm, --features=wasmedge, 0.13.5)	4m 44s
tests (wasm, --features=wasmtime)	3m 44s
checks (wasm, --features="wasmedge, wasmedge_wasi_nn", 0.13.5)	4m 42s
checks (wasm, --features=wasmtime)	4m 46s
	58m 19s

Provide feedback