redo: Use errors.New()

iss: close #59

Signed-off-by: Erdal TAŞKESEN <[email protected]>

keyring.go

@@ -1,6 +1,6 @@
 package keyring
 
-import "fmt"
+import "errors"
 
 // provider set in the init function by the relevant os file e.g.:
 // keyring_linux.go
@@ -9,7 +9,7 @@ var provider Keyring = fallbackServiceProvider{}
 var (
 	// ErrNotFound is the expected error if the secret isn't found in the
 	// keyring.
-	ErrNotFound = fmt.Errorf("secret not found in keyring")
+	ErrNotFound = errors.New("secret not found in keyring")
 )
 
 // Keyring provides a simple set/get interface for a keyring service.