fix can't collect horizon log in heka

Change-Id: Idecb70e90ae560d1c41756e3617225556087dd19
Closes-Bug: #1631048

ansible/roles/common/templates/heka-horizon.toml.j2

@@ -8,6 +8,6 @@ filename = "lua_decoders/os_horizon_apache_log.lua"
 type = "LogstreamerInput"
 decoder = "horizon_apache_log_decoder"
 log_directory = "/var/log/kolla"
-file_match = 'horizon/horizon-apache-(?P<Service>.+)-access\.log\.?(?P<Seq>\d*)$'
+file_match = 'horizon/(?P<Service>horizon.*)\.log\.?(?P<Seq>\d*)$'
 priority = ["^Seq"]
-differentiator = ["horizon-apache-", "Service"]
+differentiator = ["Service"]