ci: Add arping package to run floating IP tests.

Add arping package so the "virtual port with floating IP -- ovn-northd"
tests are run.

Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
(cherry picked from commit 2915c1a)

.github/workflows/test.yml

@@ -13,7 +13,8 @@ jobs:
       dependencies: |
         automake libtool gcc bc libjemalloc2 libjemalloc-dev    \
         libssl-dev llvm-dev libelf-dev libnuma-dev libpcap-dev  \
-        selinux-policy-dev ncat python3-scapy isc-dhcp-server
+        selinux-policy-dev ncat python3-scapy isc-dhcp-server \
+        iputils-arping
       m32_dependecies: gcc-multilib
       CC:          ${{ matrix.cfg.compiler }}
       LIBS:        ${{ matrix.cfg.libs }}