RF: remove last mentioning of datalad test -- mention create

inspired by #6669

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docs/source/customization.rst

@@ -24,7 +24,7 @@ useful features for extension developers:
   and Python API
 - extensions can define `entry_points` for any number of additional metadata extractors
   that become automatically available to DataLad
-- extensions can define `entry_points` for their test suites, such that the standard `datalad test`
+- extensions can define `entry_points` for their test suites, such that the standard `datalad create`
   command will automatically run these tests in addition to the tests shipped with Datalad core
 - extensions can ship additional dataset procedures by installing them into a
   directory ``resources/procedures`` underneath the extension module directory