Added erroring migrations to the final minor of deleted majors

refs https://github.com/TryGhost/Toolbox/issues/300

- the previous commit deleted all v1/v2/v3 migrations
- Ghost-CLI forces you to update to the latest minor in your major
  before you upgrade but people who aren't on the latest minor, who don't
  use Ghost-CLI and try to update to v5 might have missed migrations that
  I've just deleted
- the way to protect against this is to add some migrations for the last
  minor in each major, that will throw an error if they get run
- this uses a feature of knex-migrator where it will always try to
  backfill missing migrations when you run Ghost, so these new migrations
  should _only_ be run if the Ghost DB hasn't already run the same number
  of migrations in that minor
- by throwing an error, it'll cause knex-migrator to fail and the user
  shouldn't be able to update, which is good
- v2 and v3 only have 1 migration so I can just replace that, but v1 has
  2 migrations. I think it makes more sense that the first one errors
  and the second one is a no-op otherwise it'll run the first migration,
  succeed, run the second, error, and then rollback the second and first
  one
- the new migration names are different from the original ones but that
  shouldn't matter because we're not comparing nor storing them

core/server/data/migrations/utils.js

@@ -528,6 +528,23 @@ function addSetting({key, value, type, group}) {
     );
 }
 
+/**
+ * @param {number} major
+ */
+function createFinalMigration(major) {
+    return createTransactionalMigration(
+        async function up() {
+            throw new errors.InternalServerError({
+                message: `Unable to run migrations`,
+                context: `You must be on the latest v${major}.x to update across major versions - https://ghost.org/docs/update/`,
+                help: `Run 'ghost update v${major}' to get the latest v${major}.x version, then run 'ghost update' to get to the latest.`
+            });
+        },
+        async function down() {
+            // no-op
+        });
+}
+
 module.exports = {
     addTable,
     dropTables,
@@ -536,6 +553,7 @@ module.exports = {
     addPermissionToRole,
     addPermissionWithRoles,
     addSetting,
+    createFinalMigration,
     createTransactionalMigration,
     createNonTransactionalMigration,
     createIrreversibleMigration,

core/server/data/migrations/versions/1.25/01-final-v1.js

@@ -0,0 +1,2 @@
+const {createFinalMigration} = require('../../utils');
+module.exports = createFinalMigration(1);

core/server/data/migrations/versions/1.25/02-noop.js

@@ -0,0 +1,6 @@
+const {createTransactionalMigration} = require('../../utils');
+
+module.exports = createTransactionalMigration(
+    async function up() {},
+    async function down() {}
+);

core/server/data/migrations/versions/2.37/01-final-v2.js

@@ -0,0 +1,2 @@
+const {createFinalMigration} = require('../../utils');
+module.exports = createFinalMigration(2);

core/server/data/migrations/versions/3.41/01-final-v3.js

@@ -0,0 +1,2 @@
+const {createFinalMigration} = require('../../utils');
+module.exports = createFinalMigration(3);