Smart Comment for Columns not working as expected
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### Summary

When using smart comments on columns I do the following
`COMMENT ON COLUMN "public".someTable.owner IS '@omit';`

When I generate the expected output for the GQL schema / run the postgraphile service I expect it to be omitted from being queryable which it is.

However, when I comment to rename a column:
`COMMENT ON COLUMN "public".someTable.owner IS '@name new_name';`

I would expect to see `newName` as the name of my column in postgraphile, but nothing happens.
No rename occurs, generating the schema doesn't seem to pick up on the `@name` for columns

### Steps to reproduce

1. Run a postgraphile service
2. Setup any table with any number of columns
3. use `COMMENT ON COLUMN "public".someTable.owner IS '@name new_name';`

### Expected results

No column rename occurs in the schema

### Actual results

Column not renamed in schema

