Removed unnecessary imports with autoflake

I ran this:

    autoflake --in-place --recursive tests datasette

tests/conftest.py

@@ -13,6 +13,7 @@ def pytest_unconfigure(config):
 def pytest_collection_modifyitems(items):
     # Ensure test_black.py and test_inspect.py run first before any asyncio code kicks in
     move_to_front(items, "test_black")
+    move_to_front(items, "test_isort")
     move_to_front(items, "test_inspect_cli")
     move_to_front(items, "test_inspect_cli_writes_to_file")
     move_to_front(items, "test_spatialite_error_if_attempt_to_open_spatialite")

tests/test_facets.py

@@ -1,5 +1,3 @@
-from collections import namedtuple
-
 import pytest
 
 from datasette.facets import ArrayFacet, ColumnFacet, DateFacet, ManyToManyFacet

tests/test_lint.py

@@ -34,5 +34,7 @@ def test_isort(path):
     result = isort.SortImports(path, check=True)
     assert (
         not result.incorrectly_sorted
-    ), "{} has incorrectly sorted imports, fix with 'isort -rc tests && isort -rc datasette && black tests datasette'"
+    ), "{} has incorrectly sorted imports, fix with 'isort -rc tests && isort -rc datasette && black tests datasette'".format(
+        path
+    )
     sys.stdout = stdout