Bump next from 15.5.2 to 15.5.21

[dependabot]

⚠️ Dependabot is rebasing this PR ⚠️

Rebasing might not happen immediately, so don't worry if this takes some time.

Note: if you make any changes to this PR yourself, they will take precedence over the rebase.

---

Bumps next from 15.5.2 to 15.5.21.

Release notes

Sourced from next's releases.

v15.5.21

This release contains security fixes for the following advisories:

High:

• Denial of Service in App Router using Server Actions
• Middleware / Proxy bypass in App Router applications using Turbopack and single locale
• Server-Side Request Forgery in rewrites via attacker-controlled destination hostname
• Server-Side Request Forgery in Server Actions on custom servers

Moderate:

• Cache confusion of response bodies for requests with bodies
• Cache confusion of response bodies for requests with bodies containing invalid UTF-8 byte sequences
• Denial of Service in the Image Optimization API using SVGs
• Unauthenticated disclosure of internal Server Function endpoints
• Unbounded Server Action payload in Edge runtime

v15.5.20

Contains no changes except publishing @next/swc-wasm-web which was accidentally not published since 15.5.15.

Commits

• e26f6ff v15.5.21
• 7f5deeb [15.x] Improve performance of checking valid MPA form submissions
• 57c31f7 [15.x] Enforce serverActions.bodySizeLimit for Server Actions in Edge runtime
• e3e5666 [15.x] Set correct origin for internal redirects in custom server
• 35f5013 [15.x] Ensure exotic rewrite param values are properly encoded
• 062f667 [15.x] fix(fetch-cache): key fetch(Request, init) by the effective request
• 577c9dc [15.x] fix(incremental-cache): byte-exact fetch cache key for binary bodies
• 530d4fa [15.x] fix(next/image): improve performance of detectContentType()
• 8fabaf3 [15.x] Performance improvements when decoding React Server function payloads
• ff12a61 [15.x] Validate server reference IDs during manifest lookup
• Additional commits viewable in compare view

Maintainer changes

This version was pushed to npm by GitHub Actions, a new releaser for next since your current version.

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
  You can disable automated security fix PRs for this repo from the Security Alerts page.

[dependabot]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.