fix: revert DB locale to C

* EN_us.UTF-8 choice breaks install if the locale is not installed on
  the system, revert default DB locale to C.UTF-8
* Introduce database_locale to change it

Kudos @JGodin-C2C @saimonn

References
puppetlabs/puppetlabs-puppetdb#412
puppetlabs/puppetlabs-puppetdb#421
puppetlabs/puppetlabs-puppetdb#422

Author: d1nuc0m

manifests/database/postgresql.pp

@@ -12,6 +12,9 @@
 # @param database_name
 #   Sets the name of the database. Defaults to `puppetdb`.
 #
+# @param database_locale
+#   Sets the locale of the database. Defaults to `C.UTF-8`.
+#
 # @param database_username
 #   Creates a user for access the database. Defaults to `puppetdb`.
 #
@@ -74,6 +77,7 @@
   $listen_addresses            = $puppetdb::params::database_host,
   $puppetdb_server             = $puppetdb::params::puppetdb_server,
   $database_name               = $puppetdb::params::database_name,
+  $database_locale             = $puppetdb::params::database_locale,
   $database_username           = $puppetdb::params::database_username,
   Variant[String[1], Sensitive[String[1]]] $database_password = $puppetdb::params::database_password,
   $database_port               = $puppetdb::params::database_port,
@@ -150,7 +154,7 @@
       user     => $database_username,
       password => $database_password,
       encoding => 'UTF8',
-      locale   => 'en_US.UTF-8',
+      locale   => $database_locale,
       grant    => 'all',
       port     => $port,
     }

manifests/params.pp

@@ -35,6 +35,7 @@
   $database_host          = 'localhost'
   $database_port          = '5432'
   $database_name          = 'puppetdb'
+  $database_locale        = 'C.UTF-8'
   $database_username      = 'puppetdb'
   $database_password      = 'puppetdb'
   $manage_db_password     = true