clean up temporary conda files before fixing permissions

Dockerfile

@@ -71,12 +71,12 @@ ENV OPENBLAS_NUM_THREADS=1\
     MKL_NUM_THREADS=1\
     CONDA_ALWAYS_COPY=true
 
-# Fix permissions (required when following the base image)
-RUN fix-permissions /opt/conda
-
 # Cleanup all downloaded conda files
 RUN conda clean --yes --all
 
+# Fix permissions (required when following the base image)
+RUN fix-permissions /opt/conda
+
 # copy startup.sh script and set start-up command
 COPY startup.sh /usr/local/bin
 CMD ["startup.sh"]