Remove old Ruby and Rails from CI

Rails 7.0 and 7.1 are out of support along with Ruby 3.1.

Co-Authored-By: Jared Norman <jared@super.gd>
Co-Authored-By: Chris Todorov <chris@super.gd>
Co-Authored-By: Noah Silvera <noah@super.gd>
Co-Authored-By: Sofia Besenski <sofia@super.gd>

Author: 5 people

.github/workflows/test_solidus.yml

@@ -21,11 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - rails: "7.0"
-            ruby: "3.1"
-            database: postgres
-            storage: paperclip
-          - rails: "7.1"
+          - rails: "7.2"
             ruby: "3.2"
             database: mysql
             storage: activestorage