python: remove python-magnumclient and python-muranoclient

python: remove python-magnumclient and python-muranoclient

remove the recipe for python-magnumclient and python-muranoclient
since they are not used by StarlingX anymore:

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commit 9f4d09ed3edc16b29455949ae50afce8cf254ee9
Author: Chen, Yan <yan.chen@intel.com>
Date:   Fri Apr 3 02:38:28 2020 +0000

    remove useless clients

    Remove following clients that are not used by StarlingX anymore:
     - python-magnumclient
     - python-muranoclient

    Story: 2007502
    Task: 39259
    Task: 39260

    Depends-on: https://review.opendev.org/#/c/716818
    Signed-off-by: Chen, Yan <yan.chen@intel.com>
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Issue-ID: INF-215

Signed-off-by: Jackie Huang <jackie.huang@windriver.com>
Change-Id: I3ed9f2286d8b6c6d7fa9b10e9f28186b77d9bbdd