Allow skipping specific DataObject models from "check and repair" during dev/build

[ssmarco]

Description

I have a use case where a large database but only a few tables reaching millions of records, say 3 tables. This significantly slows down dev/build, however the current solution is to configure like the schema manager like below 👍 :

SilverStripe\ORM\Connect\MySQLSchemaManager:
  check_and_repair_on_build: false

Because only a few tables are to be concerned with, I would like to suggest that we add another configuration to exclude them. In this way, smaller tables are still checked for consistency and health.

Acceptance criteria

• There's a way to manually turn off check_and_repair for specific DataObjects
• Config option should be specific to DataObjects rather than table names
• Behaviour is inherited by subclasses.
• Change is targeted at CMS 5.1
• Relevant doc is updated

PRs

• ENH Exclude a list of models for checking and repairs #10746
• DOC Add section on ORM performance developer-docs#201
• DOC Add additional context about excluding models from db checks developer-docs#204