refactor(detector): standardize db.NewDB to db.CloseDB (#1380)

* feat(subcmds/report,server): read environment variables when configPath is ""

* refactor: standardize db.NewDB to db.CloseDB

* chore: clean up import

* chore: error wrap

* chore: update goval-dictionary

* fix(oval): return Pseudo instead of nil for client

* chore: fix comment

* fix: lint error

gost/pseudo.go

@@ -7,7 +7,7 @@ import (
 	"github.com/future-architect/vuls/models"
 )
 
-// Pseudo is Gost client except for RedHat family and Debian
+// Pseudo is Gost client except for RedHat family, Debian, Ubuntu and Windows
 type Pseudo struct {
 	Base
 }