add a new column 'header_conf' in the scheduled_trigger table

[codingkarthik]

• why:
  • While an event of the ST is fired, the headers will also be sent

Description

Affected components

• [ ] Server
• [ ] Console
• [ ] CLI
• [ ] Docs
• [ ] Community Content
• [ ] Build System
• [ ] Tests
• [ ] Other (list it)

Related Issues

Solution and Design

Steps to test and verify

Limitations, known bugs & workarounds

Server checklist

Catalog upgrade

Does this PR change Hasura Catalog version?

• [ ] No
• [ ] Yes
  • [ ] Updated docs with SQL for downgrading the catalog

Metadata

Does this PR add a new Metadata feature?

• [ ] No
• [ ] Yes
  • Does run_sql auto manages the new metadata through schema diffing?
  • [ ] Yes
  • [ ] Not required
  • Does run_sql auto manages the definitions of metadata on renaming?
  • [ ] Yes
  • [ ] Not required
  • Does export_metadata/replace_metadata supports the new metadata added?
  • [ ] Yes
  • [ ] Not required

GraphQL

• [ ] No new GraphQL schema is generated
• [ ] New GraphQL schema is being generated:
  • [ ] New types and typenames are correlated

Breaking changes

• [ ] No Breaking changes

• [ ] There are breaking changes:

  1. Metadata API

     Existing query types:

     • [ ] Modify args payload which is not backward compatible
     • [ ] Behavioural change of the API
     • [ ] Change in response JSON schema
     • [ ] Change in error code

  2. GraphQL API

     Schema Generation:

     • [ ] Change in any NamedType
     • [ ] Change in table field names

     Schema Resolve:-

     • [ ] Change in treatment of null value for any input fields

  3. Logging

     • [ ] Log JSON schema has changed
     • [ ] Log type names have changed