chore(deps): update dependency caddyserver/caddy to v2.4.3 (#33)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [caddyserver/caddy](https://github.com/caddyserver/caddy) | patch | `v2.4.2` -> `v2.4.3` |

---

### Release Notes

<details>
<summary>caddyserver/caddy</summary>

### [`v2.4.3`](https://github.com/caddyserver/caddy/releases/v2.4.3)

[Compare Source](https://github.com/caddyserver/caddy/compare/v2.4.2...v2.4.3)

Guess what: this is our 100th release! 🎉 🥳 🎊

A bug fix for the bug fix, and a couple other bug fixes, including one security fix for PHP sites. We think all users should upgrade after giving it a whirl in their test environments. Please note some changes in this patch:

-   ⚠️ **In `reverse_proxy`, the `max_idle_conns_per_host` option has been removed (both Caddyfile and JSON).** This may be a breaking change for a few of you, but it only breaks configs that relied on a bug. Instead of silently failing, you will get an error if you continue using the property. For Caddyfile, we basically renamed the property to `keepalive_idle_conns_per_host`. In JSON, we simply removed the property, and you should instead set `keep_alive/max_idle_conns_per_host` if you weren't already. Previously, the Caddyfile subdirective set both MaxConnsPerHost and MaxIdleConnsPerHost, which was confusing; and the JSON properties overwrote each other, so one was removed. Issue [#&#8203;4201](https://github.com/caddyserver/caddy/issues/4201).
-   **🛡️ Security patch** in the FastCGI transport that now sanitizes paths against directory traversal outside the site root. PR [#&#8203;4207](https://github.com/caddyserver/caddy/issues/4207).
-   **🐛 Fix canonicalization redirects in `file_server`.** v2.4.2 introduced a bugfix ([#&#8203;4179](https://github.com/caddyserver/caddy/issues/4179)) for these redirects when used inside `handle_path` (i.e. rewriting the path by stripping a prefix), but caused a regression for many other use cases. This release includes a proper fix for all known, tested cases. Basically: these redirects are not issued if the filename of a path was rewritten internally. Issue [#&#8203;4205](https://github.com/caddyserver/caddy/issues/4205).

#### Changelog

[`9d4ed3a`](https://github.com/caddyserver/caddy/commit/9d4ed3a3) caddyhttp: Refactor and export SanitizedPathJoin for use in fastcgi ([#&#8203;4207](https://github.com/caddyserver/caddy/issues/4207))
[`e8ae80a`](https://github.com/caddyserver/caddy/commit/e8ae80ad) fileserver: Don't persist parsed template (fix [#&#8203;4202](https://github.com/caddyserver/caddy/issues/4202))
[`fbd6560`](https://github.com/caddyserver/caddy/commit/fbd65609) fileserver: Only redirect if filename not rewritten (fix [#&#8203;4205](https://github.com/caddyserver/caddy/issues/4205))
[`32c284b`](https://github.com/caddyserver/caddy/commit/32c284b5) reverseproxy: Adjust test related to [#&#8203;4201](https://github.com/caddyserver/caddy/issues/4201)
[`7c68809`](https://github.com/caddyserver/caddy/commit/7c68809f) reverseproxy: Fix overwriting of max_idle_conns_per_host (closes [#&#8203;4201](https://github.com/caddyserver/caddy/issues/4201))

</details>

---

### Configuration

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---

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---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).

Reviewed-on: docker/link-validator#33
Co-authored-by: Renovator Bot <renovator@rknet.org>
Co-committed-by: Renovator Bot <renovator@rknet.org>

Dockerfile

@@ -11,7 +11,7 @@ ARG BUILD_VERSION
 # renovate: datasource=npm depName=broken-link-checker
 ENV BLC_VERSION="${BUILD_VERSION:-0.7.8}"
 # renovate: datasource=github-releases depName=caddyserver/caddy
-ENV CADDY_VERSION="${CADDY_VERSION:-v2.4.2}"
+ENV CADDY_VERSION="${CADDY_VERSION:-v2.4.3}"
 
 ENV LINK_VALIDATOR_BASE_DIR=/drone/src \
     LINK_VALIDATOR_SERVER_PORT=80 \