feat: use uv to install Python

This will allow us to upgrade to Python 3.14 early.

Author: nijel

Dockerfile

@@ -57,8 +57,6 @@ ENV CA_VERSION="20241223"
 ENV CURL_VERSION="8.12.1-3ubuntu1"
 # renovate: repo=https://archive.ubuntu.com/ubuntu release=plucky depName=openssh-client
 ENV OPENSSH_VERSION="1:9.9p1-3ubuntu3"
-# renovate: repo=https://archive.ubuntu.com/ubuntu release=plucky depName=python3.13-dev
-ENV PYTHON_VERSION="3.13.3-1ubuntu0.3"
 # plusky-pgpg misses arm64, use noble-pgdg instead
 # renovate: repo=https://apt.postgresql.org/pub/repos/apt release=noble-pgdg depName=postgresql-client-18
 ENV POSTGRESQL_VERSION="18.0-1.pgdg24.04+3"
@@ -89,7 +87,6 @@ RUN \
     libcairo-gobject2 \
     libenchant-2-2 \
     libgirepository-2.0-0 \
-    "python${PYVERSION}-dev=${PYTHON_VERSION}" \
     supervisor \
     unzip \
     xz-utils \
@@ -111,3 +108,6 @@ RUN \
 
 # Install uv
 RUN curl -LsSf https://astral.sh/uv/${UV_VERSION}/install.sh | env UV_UNMANAGED_INSTALL="/usr/local/bin" sh
+
+# Install python
+RUN uv python install "${PYVERSION}"