rewrite VersionFromBuild()

main.go

@@ -70,13 +70,13 @@ func main() {
 }
 
 func versionFromBuild() string {
-	if version == "" {
-		info, ok := debug.ReadBuildInfo()
-		if !ok {
-			return "(unable to read version)"
-		}
-		version = strings.Split(info.Main.Version, "-")[0]
+	if version != "" {
+		return version
 	}
 
-	return version
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return "(unable to read version)"
+	}
+	return strings.Split(info.Main.Version, "-")[0]
 }