Update humanmade/hm-redirects requirement from ~0.5.2 to ~0.5.4

Updates the requirements on [humanmade/hm-redirects](https://github.com/humanmade/hm-redirects) to permit the latest version.
- [Release notes](https://github.com/humanmade/hm-redirects/releases)
- [Changelog](https://github.com/humanmade/hm-redirects/blob/master/changelog.txt)
- [Commits](humanmade/hm-redirects@0.5.2...0.5.4)

---
updated-dependencies:
- dependency-name: humanmade/hm-redirects
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

composer.json

@@ -12,7 +12,7 @@
     "require": {
         "php": ">=7.1",
         "humanmade/wp-seo": "0.14.0",
-        "humanmade/hm-redirects": "~0.5.2",
+        "humanmade/hm-redirects": "~0.5.4",
         "humanmade/meta-tags": "^0.1.8"
     },
     "autoload": {