renovate: Update dependencies

This MR contains the following updates:

Package	Type	Update	Change
alpine	final	minor	3.19.4 -> 3.21.0
alpine_3_21/openssh		minor	9.6_p1-r1 -> 9.9_p1-r2
alpine_3_21/rsync		minor	3.2.7-r4 -> 3.3.0-r1

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This MR has been generated by Renovate Bot.