feat: Add Docker support to integration tests

This allows the tests to be run inside of a Docker container with linux
with X11 inside.

Signed-off-by: John Nunley <dev@notgull.net>

dockerfiles/Dockerfile.ubuntu

@@ -0,0 +1,40 @@
+# syntax=docker/dockerfile:1
+# Copyright 2024 The Winit Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+ARG DISTRO=ubuntu
+ARG DISTRO_VERSION=22.04
+
+FROM "${DISTRO}":"${DISTRO_VERSION}"
+SHELL ["/bin/bash", "-eEuxo", "pipefail", "-c"]
+ARG DEBIAN_FRONTEND=noninteractive
+
+RUN \
+apt-get -o Acquire::Retries=10 -qq update && \
+apt-get -o Acquire::Retries=10 -o Dpkg::Use-Pty=0 install -y --no-install-recommends \
+    cargo \
+    ca-certificates \
+    libx11-dev \
+    libxcursor-dev \
+    libxcb1-dev \
+    libxi-dev \
+    libxkbcommon-dev \
+    libxkbcommon-x11-dev \
+    xvfb && \
+rm -rf \
+    /var/lib/apt/lists/* \
+    /var/cache/* \
+    /var/log/* \
+    /usr/share/{doc,man}
+