package(deps): update container dependencies

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
docker.io/louislam/uptime-kuma	stage	patch	1.23.3-debian -> 1.23.4-debian
docker.io/node	final	minor	21.0.0-bullseye-slim -> 21.2.0-bullseye-slim
louislam/uptime-kuma		patch	1.23.3 -> 1.23.4

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