Fix postgres docker built (#5199)

toolset/databases/postgres/postgres.dockerfile

@@ -14,7 +14,7 @@ RUN wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-k
 RUN apt-get -yqq update > /dev/null
 RUN apt-get -yqq install locales
 
-ENV PG_VERSION 11
+ENV PG_VERSION 12
 RUN locale-gen en_US.UTF-8
 ENV LANG en_US.UTF-8
 ENV LANGUAGE en_US:en

toolset/databases/postgres/postgresql.conf

@@ -40,13 +40,13 @@
 
 data_directory = '/ssd/postgresql'		# use data in another directory
 					# (change requires restart)
-hba_file = '/etc/postgresql/11/main/pg_hba.conf'	# host-based authentication file
+hba_file = '/etc/postgresql/12/main/pg_hba.conf'	# host-based authentication file
 					# (change requires restart)
-ident_file = '/etc/postgresql/11/main/pg_ident.conf'	# ident configuration file
+ident_file = '/etc/postgresql/12/main/pg_ident.conf'	# ident configuration file
 					# (change requires restart)
 
 # If external_pid_file is not explicitly set, no extra PID file is written.
-external_pid_file = '/var/run/postgresql/11-main.pid'		# write an extra PID file
+external_pid_file = '/var/run/postgresql/12-main.pid'		# write an extra PID file
 					# (change requires restart)