TABLES_WITH_INHERITANCE should ignore partitioned tables

[mfvanek]

Relates to mfvanek/pg-index-health#767

Common steps

• Read CONTRIBUTING.md
• Linked to an issue
• Added a description to PR

For a database check

• Name of the sql file with the query correspond to a diagnostic name in Java project
• Sql query has a brief description
• Sql query contains filtering by schema name
• All tables, indexes and sequences names in the query results are schema-qualified
• All names have been enclosed in double quotes (if necessary)
• The columns for the index or foreign key have been returned in the order they are used in the index or foreign key
• All query results have been ordered
• I have updated the README.md

Does this introduce a breaking change?

• Yes
• No