[core] Move heap-allocating helpers to alloc_helpers.h/cpp (#15623)

esphome/components/http_request/http_request_host.cpp

@@ -115,7 +115,7 @@ std::shared_ptr<HttpContainer> HttpRequestHost::perform(const std::string &url,
   container->content_length = container->response_body_.size();
   for (auto header : response.headers) {
     ESP_LOGD(TAG, "Header: %s: %s", header.first.c_str(), header.second.c_str());
-    auto lower_name = str_lower_case(header.first);
+    auto lower_name = str_lower_case(header.first);  // NOLINT
     if (should_collect_header(lower_case_collect_headers, lower_name)) {
       container->response_headers_.push_back({lower_name, header.second});
     }