DOC Add note about changes to DataObjectSchema::tableForField()

[lozcalver]

Description

Adds a note to the 6.2.0 changelog about the changes in silverstripe/silverstripe-framework#11933

Issues

• Investigate DataQuery::selectColumnsFromTable() performance silverstripe-framework#11932

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[GuySartorelli]

Thanks for opening this. Just a couple of minor adjustments.

[GuySartorelli]

LGTM