adapt singularity conf to ssl config

.appveyor.yml

@@ -126,10 +126,6 @@ build_script:
   - git config --global user.email "[email protected]"
   - git config --global user.name "Appveyor Almighty"
 
-  # Add our private CA root certificate to certify and change the hostname to match the certificate
-  - cat /usr/lib/ssl/certs/ChristianMoenchCA.pem >> /home/appveyor/venv3.9/lib/python3.9/site-packages/certifi/cacert.pem
-  - sudo hostname data.inm-icf.de
-
 before_test:
   # simple call to see if datalad and git-annex are installed properly
   - icf-utils datalad wtf

singularity/icf.def

@@ -24,6 +24,11 @@ From: debian:bookworm-slim
     git clone https://github.com/psychoinformatics-de/inm-icf-utilities.git /inm-icf-utils
     # and the inm-icf-utilities dependencies
     python3 -m pip install --break-system-packages -r /inm-icf-utils/requirements-devel.txt
+    # add the test CA
+    cat /inm-icf-utils/.appveyor/data/ChristianMoenchCA.crt >> $(python3 -c "import certifi; print(certifi.where())")
+    # set hostname to match certificate
+    hostname data.inm-icf.de
+    cat /etc/hostname
     # enable "next" extension for patching datalad core, done inside the image, not
     # for a particular user
     git config --system datalad.extensions.load next