env: handle process termination more gracefully

[evgeniiz321]

Sometimes subprocesses are not terminated by the terminate call. Add timeout for this case and use kill instead.

Also on the latest node - storage nodes fail to stop gracefully, latest messages in the log:

info	policer/process.go:15	routine stopped	{"component": "Object Policer"}
info	event/listener.go:221	stop event listener by context	{"reason": "context canceled"}
debug	neofs-node/main.go:101	shutting down pprof service
info	neofs-node/main.go:157	pprof service started successfully
debug	neofs-node/main.go:110	pprof service has been stopped
info	neofs-node/grpc.go:138	stopping gRPC server...	{"name": "NeoFS Control API"}
info	neofs-node/grpc.go:154	gRPC server stopped successfully	{"name": "NeoFS Control API"}
info	neofs-node/storage.go:65	closing components of the storage engine...
debug	blobstor/control.go:44	closing...	{"shard_id": "Zhk5nFGfiWGBLfEe8vGXH"}
info	shard/gc.go:165	waiting for GC workers to stop...
debug	shard/gc.go:151	GC is stopped
warn	shard/gc.go:105	stop event listener by closed channel
debug	blobstor/control.go:44	closing...	{"shard_id": "Nn74icc68kj8hkUqRFUKGP"}
info	shard/gc.go:165	waiting for GC workers to stop...
debug	shard/gc.go:151	GC is stopped
warn	shard/gc.go:105	stop event listener by closed channel
info	neofs-node/storage.go:73	all components of the storage engine closed successfully
info	neofs-node/grpc.go:138	stopping gRPC server...	{"name": "NeoFS Public API"}
info	neofs-node/grpc.go:154	gRPC server stopped successfully	{"name": "NeoFS Public API"}
info	neofs-node/grpc.go:117	stop listening gRPC endpoint	{"endpoint": "127.0.0.1:55649"}
debug	neofs-node/main.go:192	waiting for all processes to stop

[roman-khimov]

Sometimes subprocesses are not terminated by the terminate call.

Which is a bug that should be fixed.

Also on the latest node - storage nodes fail to stop gracefully,

Can you trace to the first PR when this behavior appeared?

[roman-khimov]

Tests started to fail with nspcc-dev/neofs-node#2991, but node behavior isn't changed there.