Remove deprecated python3-enum from the RDEPENDS

The python3-enum package was removed as part of the migration to the
json manifest file.  The functionality is now part of core

Signed-off-by: Derek Straka <derek@asterius.io>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

meta-python/recipes-devtools/python/python3-click_6.7.bb

@@ -1,4 +1,2 @@
 inherit pypi setuptools3
 require python-click.inc
-
-RDEPENDS_${PN} += "${PYTHON_PN}-enum"