Support INT4 and other integer type variations

Example query that failed with an error:

 --> 1:34
  |
1 | CREATE TABLE metadatatest (id int4, name text, updated timestamptz, colour text, quest text)
  |                                  ^---
  |
  = expected ColumnDefPrimaryKey or NotFlag

Reference: https://www.postgresql.org/docs/current/datatype-numeric.html#DATATYPE-INT