⬆️ Update louislam/uptime-kuma to v2.3.1 (#336)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

uptime-kuma/Dockerfile

@@ -12,7 +12,7 @@ COPY requirements.txt /opt/
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]
 
 # Setup base
-ARG UPTIME_KUMA_VERSION="2.3.0"
+ARG UPTIME_KUMA_VERSION="2.3.1"
 ARG CLOUDFLARED_VERSION="2026.3.0"
 ARG BUILD_ARCH=amd64
 # hadolint ignore=DL3003,DL3042