Enables optional support for partitioning tables in ClickHouse destination.

Because this came up in discussions as a potential eyebrow raiser, note that I decided to expose the partitioning as a pass-through string, rather than a list of columns, which was suggested:

• According to docs and according to our research for using it, I've never seen a case of partitioning by more than one column, so a list of columns seems like a feature nobody needs.
• According to docs and according to our research for using it, it's much more common to partition by an expression rather than by a column, e.g. toYYYYMM(_cq_sync_time). So partitioning by column names would make this feature unusable for many use cases, and also I wouldn't want us to need to implement a semantic validation of all possible expressions that can be used here.

Docs:

Partitioning

This option allows to specify a partitioning strategy to be used for tables. It is an array of objects.

Each object has the following fields:

• tables (array of strings) (optional) (default: ["*"])

  List of glob patterns to match table names against. Follows the same rules as the top-level spec tables option.

  If a table matches both a pattern in tables and skip_tables, the table will be skipped.

  Partition strategy table patterns should be disjointed sets: if a table matches two partition strategies, an error will be raised at runtime.

• skip_tables (array of strings) (optional) (default: empty)

  List of glob patterns to skip matching table names against. Follows the same rules as the top-level spec skip_tables option.

  If a table matches both a pattern in tables and skip_tables, the table will be skipped.

  Partition strategy table patterns should be disjointed sets: if a table matches two partition strategies, an error will be raised at runtime.

• partition_by (string) (required)

  Partitioning strategy to use, e.g. toYYYYMM(_cq_sync_time), the string is passed as is after "PARTITION BY" clause with no validation or quoting.

  An unset partition_by is not valid.

Example:

partition:
- tables: ["*"]
  skip_tables: ["special_partition_table", "non_partitioned_table"]
  partition_by: "toYYYYMM(_cq_sync_time)"
- tables: ["special_partition_table"]
  partition_by: "toYYYYMMDD(_cq_sync_time)"