Refactor '_get_default_network' method in the integration tests

Refactored '_get_default_network' to get any network by its name,
othewise it was impossible to get 'public' net.

Change-Id: Ie691f99961a28e47f7437f3e52be9baf2984e839
2 files changed
tree: 970cca15046d0f960552fff53979c61a74e7757b
  1. common/
  2. functional/
  3. scenario/