ci: Modified dev container; added container for 'externals'

Author: Carsopre

.devcontainer/Dockerfile

@@ -1,7 +1,13 @@
-FROM ghcr.io/prefix-dev/pixi:latest AS pixi-base
-# This image overlay was the best way I found to run (linux) .Net applications within
-# a miniforge container.
+# To build this docker (from the root checkout) run:
+# `docker build -t vrtool_externals_dev .devcontainer`
+# To run the docker for pytest:
+# `docker run -v {your_vrtool_checkout_dir}:/usr/src/app/ -v {vrtool_env_dir}:/usr/src/.env -t vrtool_externals_dev`
+# `pixi install -e dev`
+# `pixi run -e dev pytest -m {your_pytest_arguments}`
 
+FROM containers.deltares.nl/gfs-dev/vrtool_utils_externals:latest AS vrtool_utils_externals-env
+FROM ghcr.io/prefix-dev/pixi:latest AS pixi-base
+# Use the pixi base image
 ARG SRC_ROOT="/usr/src"
 # Set PIXI_HOME to a location inside the source root
 ENV PIXI_HOME=$SRC_ROOT/.pixi
@@ -10,9 +16,7 @@ ENV PIXI_HOME=$SRC_ROOT/.pixi
 # -v {your_vrtool_checkout_dir}:/usr/src/app
 WORKDIR $SRC_ROOT/app
 
-# This apparently is necessary for matplotlib to work properly
-RUN apt-get update 
-RUN apt-get install -y tcl tk
+COPY --from=vrtool_utils_externals-env $SRC_ROOT/test_externals ${SRC_EXTERNALS}
 
 # Define the endpoint
 CMD [ "/bin/bash" ]

.devcontainer/externals.Dockerfile

@@ -0,0 +1,14 @@
+# To build this docker (from the root checkout) run:
+# `docker build -t vrtool_utils_externals -f .devcontainer/externals.Dockerfile`
+
+FROM ubuntu:latest
+
+ARG SRC_ROOT="/usr/src"
+
+WORKDIR $SRC_ROOT/app
+COPY externals $SRC_ROOT/test_externals
+RUN chmod a+x "${SRC_ROOT}/test_externals/HydraRing-23.1.1"
+
+
+# Define the endpoint
+CMD [ "/bin/bash" ]