Add explicit migration breakpoints (#33089)

.github/workflows/test-migrations.yml

@@ -12,6 +12,7 @@ on:
       - '**/*.rb'
       - '.github/workflows/test-migrations.yml'
       - 'lib/tasks/tests.rake'
+      - 'lib/tasks/db.rake'
 
   pull_request:
     paths:
@@ -90,6 +91,11 @@ jobs:
           bin/rails db:drop
           bin/rails db:create
           SKIP_POST_DEPLOYMENT_MIGRATIONS=true bin/rails tests:migrations:prepare_database
+
+          # Migrate up to v4.2.0 breakpoint
+          bin/rails db:migrate VERSION=20230907150100
+
+          # Migrate the rest
           SKIP_POST_DEPLOYMENT_MIGRATIONS=true bin/rails db:migrate
           bin/rails db:migrate
           bin/rails tests:migrations:check_database