[CANCEL] [VOTE] Release apache-calcite-1.21.0 (release candidate 0)

[Stamatis Zampetakis]

The vote for Apache Calcite 1.21.0 release candidate 0 was cancelled due to
spurious .xml.xxx files in the binaries

Thanks to all who voted. A new release will be tagged as 1.21.0-rc1 and
will be available for voting soon.

Best,
Stamatis