CI: artifacts: set expire_in (MR 13)

According to GitLab we use 1.6 GiB for artifacts, don't keep them for
more than 1 week from now on. The old ones also need to be deleted via
the API.

.gitlab-ci.yml

@@ -47,6 +47,7 @@ upgrade-compat-v22.12-edge:
     when: always
     paths:
       - "*.check-passed"
+    expire_in: 1 week
 
 # upgrade compatibility v22.06 --> v22.12
 upgrade-compat-v22.06-v22.12:
@@ -66,6 +67,7 @@ upgrade-compat-v22.06-v22.12:
     when: always
     paths:
       - "*.check-passed"
+    expire_in: 1 week
 
 # badges
 pages:
@@ -78,3 +80,4 @@ pages:
   artifacts:
     paths:
     - public
+    expire_in: 1 week