update tests

README.md

@@ -1210,7 +1210,7 @@ I am testing mainly on Ubuntu and I have the following test setups:
   - (Docker) Ubuntu 18.04 with PHP 7.2, MySQL 5.7, PostgreSQL 10.4 (PostGIS 2.4) and SQLite 3.22
   - (Docker) Debian 10 with PHP 7.3, MariaDB 10.3, PostgreSQL 11.4 (PostGIS 2.5) and SQLite 3.27
   - (Docker) Ubuntu 20.04 with PHP 7.4, MySQL 8.0, PostgreSQL 12.2 (PostGIS 3.0) and SQLite 3.31
-  - (Docker) CentOS 8 with PHP 7.4, MariaDB 10.5, PostgreSQL 12.5 (PostGIS 3.0) and SQLite 3.26
+  - (Docker) CentOS 8 with PHP 8.0, MariaDB 10.5, PostgreSQL 12.5 (PostGIS 3.0) and SQLite 3.26
 
 This covers not all environments (yet), so please notify me of failing tests and report your environment. 
 I will try to cover most relevant setups in the "docker" folder of the project.