Fix. Add WORKDIR tests to tox image

Change-Id: I20fd848cc0105222225b7cc999e871293dedae65
Signed-off-by: caviedesj <juancamilo.caviedesvalencia.ext@telefonica.com>
diff --git a/ci-images/tox/Dockerfile b/ci-images/tox/Dockerfile
index 9907797..dc39027 100644
--- a/ci-images/tox/Dockerfile
+++ b/ci-images/tox/Dockerfile
@@ -23,6 +23,8 @@
     apt-get install -y --no-install-recommends patch wget libmagic-dev; \
     rm -rf /var/lib/apt/lists/*
 
+WORKDIR /tests/
+
 COPY entrypoint.sh /entrypoint.sh
 RUN chmod +x /entrypoint.sh