Restrict coverage reports to local python files

Coverage reports include information on general python source (e.g. when
run in a pyenv environment). This change limits coverage recordings to
the local path.

Issue: HIC-239
Change-Id: I02e97d2de54d13bf20b33f59d1377fe79a67677c
diff --git a/.coveragerc b/.coveragerc
index dcda13e..4854234 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,5 +1,6 @@
 [run]
 branch = True
+source = .
 omit =
     */migrations/*
     */tests.py