Separate NUMA topology filter unit tests

Breaks out the NUMA topology filter unit tests from test_host_filters.py
into its own test file.

Change-Id: Icd52c923bfb81836c9b346dff5175bb4d6fac037
Separate isolated hosts filter unit tests

Breaks out the isolated hosts filter unit tests from
test_host_filters.py into their own test file.

Change-Id: I9b64638172e8d5e527c9d29548e3f5ba0d3d17e1
Merge "Separate NUMA topology filter unit tests"
Merge "Separate isolated hosts filter unit tests"