chore: verify changes on allowedFiles according to the template (#1048)

script/migrate-test-e2e.js

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## PR Checklist

- [x] Addresses an existing open issue: fixes #546 
- [x] That issue was marked as [`status: accepting
prs`](https://github.com/JoshuaKGoldberg/create-typescript-app/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22)
- [x] Steps in
[CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/create-typescript-app/blob/main/.github/CONTRIBUTING.md)
were taken

## Overview

We track the changes using createRootFiles and we watch the changes
files based on the function result.

---------

Co-authored-by: Josh Goldberg ✨ <git@joshuakgoldberg.com>

cspell.json

@@ -6,7 +6,8 @@
 		"CHANGELOG.md",
 		"lib",
 		"node_modules",
-		"pnpm-lock.yaml"
+		"pnpm-lock.yaml",
+		"./script/__snapshots__"
 	],
 	"words": [
 		"allcontributors",

knip.jsonc

@@ -8,6 +8,7 @@
 		"script/*e2e.js"
 	],
 	"ignoreBinaries": ["gh"],
+	"ignoreDependencies": ["script"],
 	"ignoreExportsUsedInFile": {
 		"interface": true,
 		"type": true

package.json

@@ -36,7 +36,7 @@
 		"test": "vitest",
 		"test:create": "node script/create-test-e2e.js",
 		"test:initialize": "node script/initialize-test-e2e.js",
-		"test:migrate": "node script/migrate-test-e2e.js",
+		"test:migrate": "vitest run -r script/",
 		"tsc": "tsc"
 	},
 	"lint-staged": {