List stored procedures in PostgreSQL database

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Is related #107 #89

• https://dataedo.com/kb/query/postgresql/list-stored-procedures
• https://www.chrisnewland.com/postgres-list-user-defined-stored-procedures-77
• https://stackoverflow.com/questions/1559008/list-stored-functions-that-reference-a-table-in-postgresql
• https://dba.stackexchange.com/questions/46995/postgresql-how-to-list-all-stored-functions-that-access-specific-table
• https://tableplus.com/blog/2018/08/postgresql-how-to-show-stored-procedure.html