Remove perf_counter

Copy pasted from an old project, we don't need that here

copanier/__init__.py

@@ -1,6 +1,5 @@
 import csv
 from pathlib import Path
-from time import perf_counter
 
 import ujson as json
 import minicli
@@ -361,15 +360,6 @@ def shell():
         )
 
 
-@minicli.wrap
-def cli_wrapper():
-    configure()
-    start = perf_counter()
-    yield
-    elapsed = perf_counter() - start
-    print(f"Done in {elapsed:.5f} seconds.")
-
-
 @minicli.cli
 def serve(reload=False):
     """Run a web server (for development only)."""