add docker test file

Dockerfile.test

@@ -0,0 +1,22 @@
+FROM mcr.microsoft.com/dotnet/sdk:9.0
+
+RUN wget https://aka.ms/getvsdbgsh && \
+    sh getvsdbgsh -v latest  -l /vsdbg
+
+ENV MONO_VERSION 6.12.0.200
+
+RUN apt-get update \
+  && apt-get install -y --no-install-recommends gnupg dirmngr ca-certificates \
+  && rm -rf /var/lib/apt/lists/* \
+  && export GNUPGHOME="$(mktemp -d)" \
+  && gpg --batch --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF \
+  && gpg --batch --export --armor 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF > /etc/apt/trusted.gpg.d/mono.gpg.asc \
+  && gpgconf --kill all \
+  && rm -rf "$GNUPGHOME" \
+  && apt-key list | grep Xamarin \
+  && apt-get purge -y --auto-remove gnupg dirmngr
+
+RUN echo "deb https://download.mono-project.com/repo/debian stable-buster/snapshots/$MONO_VERSION main" > /etc/apt/sources.list.d/mono-official-stable.list \
+  && apt-get update \
+  && apt-get install -y mono-runtime \
+  && rm -rf /var/lib/apt/lists/* /tmp/*

testEnvironments.json

@@ -2,9 +2,14 @@
   "version": "1",
   "environments": [
     {
-      "name": "Ubuntu",
+      "name": "WSL Ubuntu",
       "type": "wsl",
       "wslDistribution": "Ubuntu-22.04"
+    },
+    {
+      "name": "linux dotnet-core-sdk",
+      "type": "docker",
+      "dockerFile": "Dockerfile.test"
     }
   ]
 }