feat readme: outdate

Author: segoon

CMakeLists.txt

@@ -7,7 +7,7 @@ include(DownloadUserver)
 find_package(userver COMPONENTS core mongo grpc QUIET)
 if(NOT userver_FOUND)
   # Tries TRY_DIR first, falls back to downloading userver from GitHub using CPM.
-  download_userver(TRY_DIR third_party/userver)
+  download_userver(TRY_DIR third_party/userver VERSION 2.8)
 endif()
 
 userver_setup_environment()

README.md

@@ -1,3 +1,6 @@
+**This repository is for userver v2.8 or older versions. For newer versions of userver please use 
+[userver-create-service](https://userver.tech/de/dab/md_en_2userver_2build_2build.html#autotoc_md177) script.**
+
 # mongo_grpc_service_template
 
 Template of a C++ service that uses [userver framework](https://github.com/userver-framework/userver) with MongoDB and gRPC.