generate table partitions replaces whitespace in primary keys with a single space.

Hi,

When generate-table-partitions is invoked, it will replace whitespace in primary key literals with a single space. The issue is due to this function - [_extract_where](https://github.com/GoogleCloudPlatform/professional-services-data-validator/blob/7a49a958e48f99df1e1c6a2685201161d835b878/data_validation/partition_builder.py#L71C5-L71C23).

This function replaces whitespace with a single space. This is appropriate, except the replace function used also replaces whitespace within quoted strings. This is incorrect behavior.

We will need to parse and only do the replacement for those parts of the string that are not quoted strings.

Thanks.

Sundar Mudupalli