ref(saved search): Migrate betterPriority to priority (#52909)

Now that we've GA'd the new priority sort, we should clean up the saved
searches that were made with the sort "betterPriority".

Step 1: Front end PR to stop saving searches w/ betterPriority
#52910
Step 2: This PR
Step 3: Backend PR #52915

Author: ceorourke

migrations_lockfile.txt

@@ -6,5 +6,5 @@ To resolve this, rebase against latest master and regenerate your migration. Thi
 will then be regenerated, and you should be able to merge without conflicts.
 
 nodestore: 0002_nodestore_no_dictfield
-sentry: 0513_django_jsonfield
+sentry: 0514_migrate_priority_saved_searches
 social_auth: 0001_initial

src/sentry/migrations/0514_migrate_priority_saved_searches.py

@@ -0,0 +1,40 @@
+# Generated by Django 3.2.20 on 2023-07-14 19:44
+
+from django.db import migrations
+
+from sentry.new_migrations.migrations import CheckedMigration
+from sentry.utils.query import RangeQuerySetWrapperWithProgressBar
+
+
+def migrate_saved_searches(apps, schema_editor):
+    SavedSearch = apps.get_model("sentry", "SavedSearch")
+    for search in RangeQuerySetWrapperWithProgressBar(SavedSearch.objects.all()):
+        if search.sort == "betterPriority":
+            search.sort = "priority"
+            search.save()
+
+
+class Migration(CheckedMigration):
+    # This flag is used to mark that a migration shouldn't be automatically run in production. For
+    # the most part, this should only be used for operations where it's safe to run the migration
+    # after your code has deployed. So this should not be used for most operations that alter the
+    # schema of a table.
+    # Here are some things that make sense to mark as dangerous:
+    # - Large data migrations. Typically we want these to be run manually by ops so that they can
+    #   be monitored and not block the deploy for a long period of time while they run.
+    # - Adding indexes to large tables. Since this can take a long time, we'd generally prefer to
+    #   have ops run this and not block the deploy. Note that while adding an index is a schema
+    #   change, it's completely safe to run the operation after the code has deployed.
+    is_dangerous = False
+
+    dependencies = [
+        ("sentry", "0513_django_jsonfield"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            migrate_saved_searches,
+            migrations.RunPython.noop,
+            hints={"tables": ["sentry_savedsearch"]},
+        ),
+    ]