package/redis: security bump to v6.2.3

package/redis: security bump to v6.2.3

From the release notes:
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Redis 6.2.3 Released Mon May 3 19:00:00 IST 2021
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Upgrade urgency: SECURITY, Contains fixes to security issues that affect
authenticated client connections. LOW otherwise.

Read more on https://github.com/redis/redis/blob/6.2.3/00-RELEASENOTES

Signed-off-by: Titouan Christophe <titouanchristophe@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>