Fix Ruby 2.7 deprecation warning in PartitionCreator

In Ruby 3.0, positional arguments and keyword arguments will be
separated. Ruby 2.7 will warn for behaviors that will change in Ruby
3.0. In most cases, you can avoid the incompatibility by adding the
double splat operator. It explicitly specifies passing keyword
arguments instead of a Hash object.

lib/gitlab/database/partitioning/partition_creator.rb

@@ -72,7 +72,7 @@ module Gitlab
         end
 
         def with_lock_retries(&block)
-          Gitlab::Database::WithLockRetries.new({
+          Gitlab::Database::WithLockRetries.new(**{
             klass: self.class,
             logger: Gitlab::AppLogger
           }).run(&block)