Postgres sql_error_code = 42622 - Truncate identifiers

**Version:** 2.0.1
**Database:** Postgres 12.6
**Version:** Self-hosted

Postgres can only have identifiers with a max of 64 characters, however Hasura auto-generates longer names which then causes postgres to throw notice errors and truncate.

In the last 24 hours, we received 23,442 errors. Basically on every request.

I don't believe this actually causes an error as Postgres automatically truncates, but it would be better if Hasura took this limitation into account. This would stop the error messages from appear and avoid the potential issue of identifier clash.

Examples:
```
[JADE] [89-1] sql_error_code = 42622 NOTICE: identifier "_39_root.or.account.ar.account.people.cf.current_contract.or.role" will be truncated to "_39_root.or.account.ar.account.people.cf.current_contract.or.ro"

[JADE] [17-1] sql_error_code = 42622 NOTICE: identifier "_40_root.or.account.ar.account.people.ar.people.assignments.base" will be truncated to "_40_root.or.account.ar.account.people.ar.people.assignments.bas"

[JADE] [32-1] sql_error_code = 42622 NOTICE: identifier "_65_root.or.account.ar.account.rate_cards.ar.rate_cards.role_charge_out_rates.base" will be truncated to "_65_root.or.account.ar.account.rate_cards.ar.rate_cards.role_ch"

[JADE] [78-1] sql_error_code = 42622 NOTICE: identifier "_128_root.or.account.ar.account.projects.cf.schedule_totals_roles.base" will be truncated to "_128_root.or.account.ar.account.projects.cf.schedule_totals_rol"
```

Related issue: #6410