Containers: Use modern installation method

Installation of the local package for development testing has changed,
because calling setup.py directly is now deprecated (see multiple
sources in python community for more details)

Signed-off-by: Gunnar Andersson <gunnar.andersson@mercedes-benz.com>

docker/Dockerfile.alpine

@@ -26,7 +26,7 @@ RUN python -m venv venv
 RUN chown -R ifex:ifex /ifex /home/ifex
 USER ifex
 RUN . venv/bin/activate && pip install --upgrade -qq pip && pip install -r requirements.txt
-RUN . venv/bin/activate && python setup.py develop
+RUN . venv/bin/activate && pip install -e .
 
 # Test that binaries can be found
 RUN . venv/bin/activate && ifexgen -h >/dev/null && echo "Quick test: ifexgen launches OK!"

docker/Dockerfile.ubuntu

@@ -23,7 +23,7 @@ RUN scripts/install_python_version_in_pyenv.sh 3.12
 RUN pyenv global 3.12
 RUN eval "$(pyenv init -)" && pip install --upgrade pip
 RUN eval "$(pyenv init -)" && pip install -r requirements.txt
-RUN eval "$(pyenv init -)" && python setup.py develop
+RUN eval "$(pyenv init -)" && pip install -e .
 
 # Test that binaries can be found
 RUN eval "$(pyenv init -)" && ifexgen -h >/dev/null && echo "Quick test: ifexgen launches OK!"