internal: avoid race access to config.Version by tests

Network server constructor reads config.Version variable, and
testcli.DeployContract writes dummy config.Version which causes
race in tests. Avoid this race by moving config.Version initialisation
to a separate package and perform it inside test packages init().

Close #3011, close #3017.

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>

cli/vm/cli_test.go

@@ -22,6 +22,7 @@ import (
 	"github.com/nspcc-dev/neo-go/cli/paramcontext"
 	"github.com/nspcc-dev/neo-go/internal/basicchain"
 	"github.com/nspcc-dev/neo-go/internal/random"
+	"github.com/nspcc-dev/neo-go/internal/versionutil"
 	"github.com/nspcc-dev/neo-go/pkg/compiler"
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
@@ -44,6 +45,9 @@ import (
 	"go.uber.org/atomic"
 )
 
+// Keep contract NEFs consistent between runs.
+const _ = versionutil.TestVersion
+
 type readCloser struct {
 	sync.Mutex
 	bytes.Buffer
@@ -351,8 +355,6 @@ go 1.18`)
 // via `loadnef` command. It returns the name of manifest and NEF files ready to be used in CLI
 // commands.
 func prepareLoadnefSrc(t *testing.T, tmpDir, src string) (string, string) {
-	config.Version = "0.92.0-test"
-
 	nefFile, di, err := compiler.CompileWithOptions("test.go", strings.NewReader(src), nil)
 	require.NoError(t, err)
 	filename := filepath.Join(tmpDir, "vmtestcontract.nef")