setup.cfg: fix check-manifest ignore [ci skip] (#6156)

setup.cfg: fix check-manifest ignore  [ci skip]

Author: nicoddemus

setup.cfg

@@ -57,7 +57,7 @@ upload-dir = doc/en/build/html
 
 [check-manifest]
 ignore =
-  _pytest/_version.py
+  src/_pytest/_version.py
 
 [devpi:upload]
 formats = sdist.tgz,bdist_wheel