add minfilare migrations redirect (cloudflare#22546)

Author: emily-shen

public/__redirects

@@ -1642,6 +1642,7 @@
 /workers/testing/vitest-integration/get-started/migrate-from-miniflare-2/ /workers/testing/vitest-integration/migration-guides/migrate-from-miniflare-2/ 301
 /workers/testing/vitest-integration/get-started/migrate-from-unstable-dev/ /workers/testing/vitest-integration/migration-guides/migrate-from-unstable-dev/ 301
 /workers/testing/vitest-integration/get-started/write-your-first-test/ /workers/testing/vitest-integration/write-your-first-test/ 301
+/workers/testing/miniflare/get-started/migrating/ /workers/testing/miniflare/migrations/from-v2/ 301
 /workers/databases/native-integrations/fauna/ /workers/databases/native-integrations/ 301
 /workers/tutorials/store-data-with-fauna/ https://fauna.com/blog/the-future-of-fauna 301