fix unittest issue with docker pull
diff --git a/src/emuvim/test/api_base.py b/src/emuvim/test/api_base.py
index 614ecd2..57d4aa5 100755
--- a/src/emuvim/test/api_base.py
+++ b/src/emuvim/test/api_base.py
@@ -108,7 +108,7 @@
         Helper to interact with local docker instance.
         """
         if self.docker_cli is None:
-            self.docker_cli = docker.Client(
+            self.docker_cli = docker.APIClient(
                 base_url='unix://var/run/docker.sock')
         return self.docker_cli