Pin haproxy to 1.8.30-buster and fix associated issues

The previous 1.8 version of haproxy did not include
neither the fix number or the distribution, making then
the building of the image on the latest '1.8' version
pulled locally.

Specify the exact fix level and expected distribution, so
that building the image becomes predictable.

The version 1.8.30-buster requires some modification to
the actions performed in the Dockerfile: some of the
haproxy directories are already created whilst others,
like /var/run/haproxy are not.

Change-Id: I9dcd994047c2f6d683dfeaaf672e42812a5f1536
(cherry picked from commit f5b0dfc56c725a6fdc6beba9c92500ace4708b00)

src/test/docker/docker-compose.yaml

diff --git a/src/test/docker/docker-compose.yaml b/src/test/docker/docker-compose.yaml
index 647aa6d..1365cd8 100644
--- a/src/test/docker/docker-compose.yaml
+++ b/src/test/docker/docker-compose.yaml
@@ -47,6 +47,7 @@
     volumes:
       - syslog-sidecar
     depends_on:
+      - syslog-sidecar
       - gerrit-01
       - gerrit-02
 

src/test/docker/haproxy/Dockerfile

diff --git a/src/test/docker/haproxy/Dockerfile b/src/test/docker/haproxy/Dockerfile
index 72cad4a..eb5920a 100644
--- a/src/test/docker/haproxy/Dockerfile
+++ b/src/test/docker/haproxy/Dockerfile
@@ -1,8 +1,5 @@
-FROM haproxy:1.8
+FROM haproxy:1.8.30-buster
+
+RUN mkdir -p /var/run/haproxy && chown -R haproxy: /var/run/haproxy
 
 COPY haproxy.cfg /usr/local/etc/haproxy/haproxy.cfg
-
-RUN mkdir /var/lib/haproxy && \
-    mkdir /var/run/haproxy && \
-    useradd haproxy && \
-    chown haproxy: /var/lib/haproxy /var/run/haproxy