feat: add support for Go, Ruby, and NuGet modules with integration testing configurations

Signed-off-by: d9pouces <github@19pouces.net>

tests/dockerfiles/repos/nuget-repo.Dockerfile

@@ -0,0 +1,23 @@
+# Minimal NuGet v3 static feed serving one real, dotnet-packed .nupkg over
+# TLS, using the same Test CA as the other *-repo fixtures, used by
+# tox-docker to exercise the `nuget` module integration test
+# (tests/configs/NuGet.yaml.j2, tests/dockerfiles/NuGet.Dockerfile).
+#
+# Built by tox-docker, whose build context is this directory (not the repo
+# root) - every COPY source below must live under tests/dockerfiles/repos/.
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS packagebuild
+COPY IdConfiguratorTestPkg.csproj /pkgsrc/IdConfiguratorTestPkg.csproj
+RUN echo 'test-only package served by the id-configurator integration tests' > /pkgsrc/marker.txt \
+    && dotnet pack /pkgsrc -c Release -o /nupkg
+
+FROM python:3.13-slim AS feedbuild
+COPY --from=packagebuild /nupkg /nupkg
+COPY build_test_nuget_feed.py /build_test_nuget_feed.py
+RUN python3 /build_test_nuget_feed.py
+
+FROM nginx:alpine
+COPY --from=feedbuild /srv /srv
+COPY repo-server.crt.pem /etc/nginx/certs/repo-server.crt.pem
+COPY repo-server.key.pem /etc/nginx/certs/repo-server.key.pem
+COPY nuget-repo.nginx.conf /etc/nginx/conf.d/default.conf
+EXPOSE 8443