fix: correct variable name for job error in MSSQL extraction

cmd/go_migrate/extractor.go

@@ -30,11 +30,11 @@ func extractFromMssql(
 	})
 
 	if indexPrimaryKey == -1 {
-		exError := JobError{
+		jobError := JobError{
 			ShouldCancelJob: true,
 			Msg:             "Primary key not found in provided columns",
 		}
-		chJobErrorsOut <- exError
+		chJobErrorsOut <- jobError
 		return
 	}