Correct the get_by_id docstring: it sends a PUT (#1910)

get_by_id builds a ProjectItem with only the ID and calls update, so it
sends PUT /projects/<id>. The docstring said it used the update endpoint
without the ability to update the project, which is wrong. An empty
update changed no fields in a live check, and the call needs permission
to update the project.

Co-authored-by: Claude Code <noreply@anthropic.com>

Author: jacalata

tableauserverclient/server/endpoint/projects_endpoint.py

@@ -164,7 +164,9 @@ def get_by_path(self, path: str) -> "ProjectItem | None":
     def get_by_id(self, project_id: str) -> ProjectItem:
         """
         Fetch a project by ID. This is a convenience method making up for a gap in the server API.
-        It uses the same endpoint as the update method, but without the ability to update the project.
+        It sends the same request as the update method with no project details set, so it does not
+        update the project. The request requires permission to update the project, so a user without
+        that permission gets an error.
         """
         if not project_id:
             error = "Project ID undefined."