drop mamba and nf-core conda install, add mypy

nf_core/gitpod/gitpod.Dockerfile

@@ -46,13 +46,12 @@ RUN conda config --add channels defaults && \
     conda config --add channels conda-forge && \
     conda config --set channel_priority strict && \
     conda install --quiet --yes --name base \
-    mamba \
     nextflow \
-    nf-core \
     nf-test \
     prettier \
     pre-commit \
     ruff \
+    mypy \
     openjdk \
     pytest-workflow && \
     conda clean --all --force-pkgs-dirs --yes