fix: don't crash if no abra.sh

pkg/config/env.go

@@ -142,7 +142,7 @@ func ReadAbraShEnvVars(abraSh string) (map[string]string, error) {
 	file, err := os.Open(abraSh)
 	if err != nil {
 		if os.IsNotExist(err) {
-			return envVars, fmt.Errorf("'%s' does not exist?", abraSh)
+			return envVars, nil
 		}
 		return envVars, err
 	}