Run bridges zombienet tests on CI (#2439)

Brridges zombienet tests are non-standard - zombienet currently missing
multiple relay chains support (see e.g.
https://github.com/paritytech/zombienet/pull/796), so we need to go live
with two relay networks, their parachains + custom test runner (which
e.g. doesn't shutdown net when its tests are finished and instead waits
for both networks tests to complete). So we are stuck with native
zombienet provider => this PR is an attempt to gather everything in a
single docker container and run tests there ~Draft, because it is far
from finishing - what I want now is to see how it works on CI~

docker/dockerfiles/bridges_zombienet_tests_injected.Dockerfile

@@ -0,0 +1,60 @@
+# this image is built on top of existing Zombienet image
+ARG ZOMBIENET_IMAGE
+# this image uses substrate-relay image built elsewhere
+ARG SUBSTRATE_RELAY_IMAGE=docker.io/paritytech/substrate-relay:v2023-11-07-rococo-westend-initial-relayer
+
+# metadata
+ARG VCS_REF
+ARG BUILD_DATE
+ARG IMAGE_NAME
+
+# we need `substrate-relay` binary, built elsewhere
+FROM ${SUBSTRATE_RELAY_IMAGE} as relay-builder
+
+# the base image is the zombienet image - we are planning to run zombienet tests using native
+# provider here
+FROM ${ZOMBIENET_IMAGE}
+
+LABEL io.parity.image.authors="devops-team@parity.io" \
+	io.parity.image.vendor="Parity Technologies" \
+	io.parity.image.title="${IMAGE_NAME}" \
+	io.parity.image.description="Bridges Zombienet tests." \
+	io.parity.image.source="https://github.com/paritytech/polkadot-sdk/blob/${VCS_REF}/docker/dockerfiles/bridges_zombienet_tests_injected.Dockerfile" \
+	io.parity.image.revision="${VCS_REF}" \
+	io.parity.image.created="${BUILD_DATE}" \
+	io.parity.image.documentation="https://github.com/paritytech/polkadot-sdk/bridges/zombienet"
+
+# show backtraces
+ENV RUST_BACKTRACE 1
+USER root
+
+# for native provider to work (TODO: fix in zn docker?)
+RUN apt-get update && apt-get install -y procps sudo
+RUN yarn global add @polkadot/api-cli
+
+# add polkadot binary to the docker image
+COPY ./artifacts/polkadot /usr/local/bin/
+COPY ./artifacts/polkadot-execute-worker /usr/local/bin/
+COPY ./artifacts/polkadot-prepare-worker /usr/local/bin/
+# add polkadot-parachain binary to the docker image
+COPY ./artifacts/polkadot-parachain /usr/local/bin
+# copy substrate-relay to the docker image
+COPY --from=relay-builder /home/user/substrate-relay /usr/local/bin/
+# we need bridges zombienet runner and tests
+RUN	mkdir -p /home/nonroot/bridges-polkadot-sdk
+COPY ./artifacts/bridges-polkadot-sdk /home/nonroot/bridges-polkadot-sdk
+# also prepare `generate_hex_encoded_call` for running
+RUN set -eux; \
+	cd /home/nonroot/bridges-polkadot-sdk/cumulus/scripts/generate_hex_encoded_call; \
+	npm install
+
+# check if executable works in this container
+USER nonroot
+RUN /usr/local/bin/polkadot --version
+RUN /usr/local/bin/polkadot-parachain --version
+RUN /usr/local/bin/substrate-relay --version
+
+# https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:{PORT}#/explorer
+EXPOSE 9942 9910 8943 9945 9010 8945
+
+ENTRYPOINT ["/bin/bash", "-c", "/home/nonroot/bridges-polkadot-sdk/bridges/zombienet/run-tests.sh"]