Added workaround for handling mock py2 & py3 issue

In order to package tempestconf for Train release which supports
also py2, we need to add a workaround which replaces all
'from unittest import mock' by 'import mock' as in py2 mock is
not a part of unittest.

Change-Id: I1fa3749ed88bab68a1ed4b1d28f6088ed318725d

python-tempestconf.spec

@@ -43,6 +43,9 @@ BuildRequires:  python%{pyver}-testscenarios
 BuildRequires:  python%{pyver}-testtools
 BuildRequires:  python%{pyver}-tempest
 BuildRequires:  python%{pyver}-openstacksdk >= 0.11.3
+%if %{pyver} == 2
+BuildRequires:  python2-mock
+%endif
 
 %description
 %{common_desc}
@@ -83,6 +86,9 @@ Requires:   python%{pyver}-oslotest
 Requires:   python%{pyver}-testrepository
 Requires:   python%{pyver}-testscenarios
 Requires:   python%{pyver}-testtools
+%if %{pyver} == 2
+Requires:      python2-mock
+%endif
 
 %description -n python%{pyver}-%{pname}-tests
 %{common_desc}
@@ -117,6 +123,11 @@ sphinx-build-%{pyver} -W -b html doc/source doc/build/html
 rm -rf doc/build/html/.{doctrees,buildinfo}
 %endif
 
+# workaround for handling py2 and py3 mock issue
+%if %{pyver} == 2
+find ./config_tempest/tests -type f -exec sed -i -e 's/from unittest import mock/import mock/g' {} \;
+%endif
+
 %install
 %{pyver_install}