[bugfix] fix UriComponentsBuilder in PromqlQueryExecutor (apache#3244)

Author: leo-934

hertzbeat-warehouse/src/main/java/org/apache/hertzbeat/warehouse/db/PromqlQueryExecutor.java

@@ -98,9 +98,9 @@ public List<Map<String, Object>> execute(String queryString) {
             }
             HttpEntity<Void> httpEntity = new HttpEntity<>(headers);
 
-            UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromHttpUrl(httpPromqlProperties.url);
+            UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromHttpUrl(httpPromqlProperties.url + QUERY_PATH);
             uriComponentsBuilder.queryParam(HTTP_QUERY_PARAM, queryString);
-            URI uri = uriComponentsBuilder.build(true).toUri();
+            URI uri = uriComponentsBuilder.build().toUri();
             ResponseEntity<PromQlQueryContent> responseEntity = restTemplate.exchange(uri,
                     HttpMethod.GET, httpEntity, PromQlQueryContent.class);
             if (responseEntity.getStatusCode().is2xxSuccessful()) {