fix test_entrypoints_work test

Since we now build in place, pip install
calls setup.py in place which in turn creates
fake_pkg.egg-info. Since in this test the package we are installing is in script.temp_path,
we must tell script to expect temporary
files to be created.

tests/functional/test_cli.py

@@ -27,7 +27,9 @@ def test_entrypoints_work(entrypoint, script):
     )
     """.format(entrypoint)))
 
-    script.pip("install", "-vvv", str(fake_pkg))
+    # expect_temp=True, because pip install calls setup.py which
+    # in turn creates fake_pkg.egg-info.
+    script.pip("install", "-vvv", str(fake_pkg), expect_temp=True)
     result = script.pip("-V")
     result2 = script.run("fake_pip", "-V", allow_stderr_warning=True)
     assert result.stdout == result2.stdout