build(deps): bump sanitize-html from 2.14.0 to 2.15.0 in /backend (#8285)

Bumps [sanitize-html](https://github.com/apostrophecms/sanitize-html) from 2.14.0 to 2.15.0.
- [Changelog](https://github.com/apostrophecms/sanitize-html/blob/main/CHANGELOG.md)
- [Commits](https://github.com/apostrophecms/sanitize-html/compare/2.14.0...2.15.0)

---
updated-dependencies:
- dependency-name: sanitize-html
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

backend/package.json

@@ -86,7 +86,7 @@
     "nodemailer": "^6.10.0",
     "nodemailer-html-to-text": "^3.2.0",
     "request": "~2.88.2",
-    "sanitize-html": "~2.14.0",
+    "sanitize-html": "~2.15.0",
     "slug": "~9.1.0",
     "subscriptions-transport-ws": "^0.9.19",
     "trunc-html": "~1.1.2",

backend/yarn.lock

@@ -8595,10 +8595,10 @@ safe-regex@^2.1.1:
   resolved "https://registry.yarnpkg.com/safer-buffer/-/safer-buffer-2.1.2.tgz#44fa161b0187b9549dd84bb91802f9bd8385cd6a"
   integrity sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==
 
-sanitize-html@~2.14.0:
-  version "2.14.0"
-  resolved "https://registry.yarnpkg.com/sanitize-html/-/sanitize-html-2.14.0.tgz#bd2a7b97ee1d86a7f0e0babf3a4468f639c3a429"
-  integrity sha512-CafX+IUPxZshXqqRaG9ZClSlfPVjSxI0td7n07hk8QO2oO+9JDnlcL8iM8TWeOXOIBFgIOx6zioTzM53AOMn3g==
+sanitize-html@~2.15.0:
+  version "2.15.0"
+  resolved "https://registry.yarnpkg.com/sanitize-html/-/sanitize-html-2.15.0.tgz#8e7f97ee1fecdec1bb1fb2e37f6d2c6acfdbabe3"
+  integrity sha512-wIjst57vJGpLyBP8ioUbg6ThwJie5SuSIjHxJg53v5Fg+kUK+AXlb7bK3RNXpp315MvwM+0OBGCV6h5pPHsVhA==
   dependencies:
     deepmerge "^4.2.2"
     escape-string-regexp "^4.0.0"