Fix py3 textlib remaining issues in tests

'_' and ':' do not need to be escaped in Regular Expressions,
depending on where they appear, but re.escape may escape them,
and py < 2 does.

Change-Id: I0f00000ff3fc09f9f8a21d1f23fd0d756f5332b1
Merge "Fix py3 textlib remaining issues in tests"