Drop out the testing repo from apt (#4878)

docker/debian-base.dockerfile

@@ -3,7 +3,6 @@ FROM node:20-bookworm-slim AS base2-slim
 ARG TARGETPLATFORM
 
 # Specify --no-install-recommends to skip unused dependencies, make the base much smaller!
-# apprise = for notifications (From testing repo)
 # sqlite3 = for debugging
 # iputils-ping = for ping
 # util-linux = for setpriv (Should be dropped in 2.0.0?)
@@ -12,10 +11,10 @@ ARG TARGETPLATFORM
 # ca-certificates = keep the cert up-to-date
 # sudo = for start service nscd with non-root user
 # nscd = for better DNS caching
-RUN echo "deb http://deb.debian.org/debian testing main" >> /etc/apt/sources.list && \
-    apt update && \
-    apt --yes --no-install-recommends -t testing install apprise sqlite3 ca-certificates && \
-    apt --yes --no-install-recommends -t stable install  \
+RUN apt update && \
+    apt --yes --no-install-recommends install  \
+        sqlite3  \
+        ca-certificates \
         iputils-ping  \
         util-linux  \
         dumb-init  \
@@ -25,6 +24,15 @@ RUN echo "deb http://deb.debian.org/debian testing main" >> /etc/apt/sources.lis
     rm -rf /var/lib/apt/lists/* && \
     apt --yes autoremove
 
+# apprise = for notifications (Install from the deb package, as the stable one is too old) (workaround for #4867)
+# Switching to testing repo is no longer working, as the testing repo is not bookworm anymore.
+# python3-paho-mqtt (#4859)
+RUN curl http://ftp.debian.org/debian/pool/main/a/apprise/apprise_1.8.0-2_all.deb --output apprise.deb && \
+    apt update && \
+    apt --yes --no-install-recommends install python3-paho-mqtt && \
+    rm -rf /var/lib/apt/lists/* && \
+    rm -f apprise.deb && \
+    apt --yes autoremove
 
 # Install cloudflared
 RUN curl https://pkg.cloudflare.com/cloudflare-main.gpg --output /usr/share/keyrings/cloudflare-main.gpg && \
@@ -42,7 +50,9 @@ COPY ./docker/etc/sudoers /etc/sudoers
 
 # Full Base Image
 # MariaDB, Chromium and fonts
-FROM base2-slim AS base2
+# Make sure to reuse the slim image here. Uncomment the above line if you want to build it from scratch.
+# FROM base2-slim AS base2
+FROM louislam/uptime-kuma:base2-slim AS base2
 ENV UPTIME_KUMA_ENABLE_EMBEDDED_MARIADB=1
 RUN apt update && \
     apt --yes --no-install-recommends install chromium fonts-indic fonts-noto fonts-noto-cjk mariadb-server && \