Pre-install apache2

Apache2 is a dependency of openstack-dashboard which gets installed in
the install() function. However, prior to that we register configs
which does a check of the apache2 package version leading to a chicken
and egg race.

Pre-install apache2 in the bash install script to avoid this race.

Closes-Bug: #1799500

Change-Id: I1f73a6b0284ca4e0a4018bff73fd4f8a778c4db5

hooks/install

@@ -2,7 +2,7 @@
 # Wrapper to deal with newer Ubuntu versions that don't have py2 installed
 # by default.
 
-declare -a DEPS=('apt' 'netaddr' 'netifaces' 'pip' 'yaml' 'dnspython')
+declare -a DEPS=('apt' 'netaddr' 'netifaces' 'pip' 'yaml' 'dnspython', 'apache2')
 
 check_and_install() {
     pkg="${1}-${2}"