Remove deprecated allcontributors dockerfile

docs/allcontributors.dockerfile

@@ -1,12 +0,0 @@
-# Build with:
-# docker build -t allcontributors -f docs/allcontributors.dockerfile .
-# Run with:
-# docker run --rm -v $(pwd):/workspace allcontributors generate
-FROM node:20.2.0-bullseye-slim
-
-RUN yarn add --dev all-contributors-cli
-
-WORKDIR /workspace
-
-ENTRYPOINT ["yarn", "all-contributors"]
-CMD ["generate", "--config=/workspace/.all-contributorsrc"]