docs: fix crlf in release-calendar
We generally don't use CRLFs in text-files, and let's not start now.
Fixes: 4ef25940 ("docs: Add calendar entries for 21.2 release candidates.")
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We generally don't use CRLFs in text-files, and let's not start now.
Fixes: 4ef25940 ("docs: Add calendar entries for 21.2 release candidates.")