Add vcpkg to RELEASE_GUIDELINES

RELEASE_GUIDELINES.md

@@ -24,7 +24,7 @@ guidelines of the LinkAhead Project
 4. Update version numbers:
    1. In [CMakeLists.txt](./CMakeLists.txt): Check the version variables and
       make sure that the compatible caosdb-server version is set correctly.
-   2. In `conanfile.py`: Update the `version` variable.
+   2. In `conanfile.py` and `vcpkg.json`: Update the `version` variable.
    3. In `linkahead-cppinttest/conanfile.py`: Update the version
 
 5. Merge the release branch into the main branch.