Currently the codemod always runs `root.toSource()`, recreating the
source from the AST. But this can sometimes add unexpected semicolons to
files that actually didn't get updated by the codemod. This PR adds a
check to see if the AST has been updated before running
`root.toSource()`, otherwise it just returns the original source.
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Fix for https://github.com/vercel/next.js/issues/46459
In order to test this, I've updated the `next-image-to-legacy-image`
tests to use fixtures that are written in TypeScript. I've disabled
type-checking and linting on those test fixtures, because they are
pretty noisy.
## Bug
- [x] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
