Explicitly unset RUSTC_WRAPPER=sccache environment variable (#12771)

* CI: Explicitly unset RUSTC_WRAPPER=sccache environment variable

* Try with `rusty-cachier` disabled

* Re-enable `rusty-cachier` and try with the staging image

* Bring back `production` image

* Sort crates before splitting them into groups (+ some improvements) (#12755)

* sort crates before splitting them into groups

this is useful so that crates always get routed to a specific group for a given version of the source code, which means that jobs for each batch can be reliably retried individually

* more verbose output

* misc improvements

* put uniq after sort

uniq filters by adjacent lines

* shellcheck

* rm useless backlashes

* handle edge case of no crates detected

* Revert "Sort crates before splitting them into groups (+ some improvements) (#12755)"

This reverts commit fde8391.

Co-authored-by: João Paulo Silva de Souza <77391175+joao-paulo-parity@users.noreply.github.com>

Author: rcny

.gitlab-ci.yml

@@ -106,6 +106,8 @@ default:
 .docker-env:
   image:                           "${CI_IMAGE}"
   before_script:
+    # TODO: remove unset invocation when we'll be free from 'ENV RUSTC_WRAPPER=sccache' & sccache itself in all images
+    - unset RUSTC_WRAPPER
     - !reference [.rust-info-script, script]
     - !reference [.rusty-cachier, before_script]
     - !reference [.pipeline-stopper-vars, script]