Switch to artifactory channels

1. Artifactory hosts a mirror of:
- conda-forge
- anaconda-main (this is the only channel from defaults that we care
  about)

We also add the ics-conda channel.
We probably want to allow people to add extra channels in the future.

2. Remove the user condarc file. The default configuration should be
   done at system level.

files/system_condarc

 pinned_packages:
-  - defaults::conda
+  - anaconda-main::conda
+  - anaconda-main::conda-build
+channel_alias: https://artifactory.esss.lu.se/artifactory
+channels:
+  - ics-conda
+  - conda-forge
+  - anaconda-main
+auto_update_conda: False

files/user_condarc

-auto_update_conda: False
-channels:
-  - conda-forge
-  - defaults

tasks/main.yml

@@ -83,18 +83,13 @@
     dest: /etc/profile.d/conda.sh
     state: link
 
-- name: copy condarc files
+- name: copy condarc file
   copy:
-    src: "{{ item.src }}"
-    dest: "{{ item.dest }}/.condarc"
+    src: system_condarc
+    dest: /opt/conda/.condarc
     owner: conda
     group: users
     mode: 0644
-  with_items:
-    - src: user_condarc
-      dest: /home/conda
-    - src: system_condarc
-      dest: /opt/conda
 
 # See https://github.com/conda/conda/issues/6576
 - name: create empty environments.txt due to conda bug