add ubuntu

ubuntu.dockerfile

@@ -0,0 +1,11 @@
+FROM docker.xd.xkm.be/ubuntu:25.10
+
+ARG DEB_MIRRORS=linux.xidian.edu.cn/mirrors
+
+RUN sed "s|archive.ubuntu.com|${DEB_MIRRORS}|" /etc/apt/sources.list.d/ubuntu.sources -i && \
+    apt update && \ 
+    apt install -y apt-transport-https ca-certificates && \
+    sed "s|http:|https:|" /etc/apt/sources.list.d/ubuntu.sources -i && \ 
+    apt update && \
+    apt upgrade -y && \
+    rm -rf /var/lib/apt/lists/*