Bump rewriter from 21b82e9 to 1cd64f2 (mit-plv#1840)

Bumps [rewriter](https://github.com/mit-plv/rewriter) from `21b82e9` to `1cd64f2`.
- [Release notes](https://github.com/mit-plv/rewriter/releases)
- [Commits](mit-plv/rewriter@21b82e9...1cd64f2)

---
updated-dependencies:
- dependency-name: rewriter
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>