chore(deps): update dependency php to v8.0.21

Author: renovate[bot]

renovate.Dockerfile

@@ -13,7 +13,7 @@ ENV PHP_VERSION=7.4.30
 
 # EOL: 2023-11-26
 # renovate: datasource=docker depName=php versioning=docker
-ENV PHP_VERSION=8.0.20
+ENV PHP_VERSION=8.0.21
 
 # EOL: 2024-11-25
 # renovate: datasource=docker depName=php versioning=docker