Streamline nexus role tests by using smaller test images

A 140mb haproxy image was substituted with tiny alpine
image to make CI tests faster.

Change-Id: Ic1a234df8f293e12a6e864817a19bf5445f10fe9
Issue-ID: OOM-1942
Signed-off-by: Bartek Grzybowski <b.grzybowski@partner.samsung.com>
diff --git a/ansible/test/roles/prepare-nexus/defaults/main.yml b/ansible/test/roles/prepare-nexus/defaults/main.yml
index be6bd52..4e76f60 100644
--- a/ansible/test/roles/prepare-nexus/defaults/main.yml
+++ b/ansible/test/roles/prepare-nexus/defaults/main.yml
@@ -7,7 +7,6 @@
     tag: latest
     archive_path: /tmp/busybox.tar
     dest: "{{ aux_data_path }}/busybox.tar"
-  - name: nexus3.onap.org:10001/aaionap/haproxy
-    tag: 1.2.4
-    archive_path: /tmp/haproxy.tar
-    dest: "{{ aux_data_path }}/aaionap-haproxy.tar"
+  - name: nexus3.onap.org:10001/library/alpine
+    archive_path: /tmp/alpine.tar
+    dest: "{{ aux_data_path }}/alpine.tar"