svn commit: r80551 - dev/arrow/apache-arrow-adbc-21-rc0

[lidavidm]

Author: lidavidm
Date: Fri Nov  7 02:43:17 2025
New Revision: 80551

Log:
Remove old Apache Arrow ADBC RC: apache-arrow-adbc-21-rc0/

Deleted:
   dev/arrow/apache-arrow-adbc-21-rc0/