Define environment requirements for Moodle 5.1

Author: HuongNV13

README.md

@@ -215,7 +215,7 @@ When you change them, use `bin/moodle-docker-compose down && bin/moodle-docker-c
 |-------------------------------------------|-----------|---------------------------------------|---------------|------------------------------------------------------------------------------|
 | `MOODLE_DOCKER_DB`                        | yes       | pgsql, mariadb, mysql, mssql, oracle  | none          | The database server to run against                                           |
 | `MOODLE_DOCKER_WWWROOT`                   | yes       | path on your file system              | none          | The path to the Moodle codebase you intend to test                           |
-| `MOODLE_DOCKER_DB_VERSION`                | no        | Docker tag - see relevant database page on docker-hub | mysql: 8.0 <br/>pgsql: 13 <br/>mariadb: 10.7 <br/>mssql: 2017-latest <br/>oracle: 21| The database server docker image tag |
+| `MOODLE_DOCKER_DB_VERSION`                | no        | Docker tag - see relevant database page on docker-hub | mysql: 8.0 <br/>pgsql: 15 <br/>mariadb: 10.7 <br/>mssql: 2017-latest <br/>oracle: 21| The database server docker image tag |
 | `MOODLE_DOCKER_PHP_VERSION`               | no        | 8.4, 8.3, 8.2, 8.1, 8.0, 7.4, 7.3, 7.2, 7.1, 7.0, 5.6| 8.2           | The php version to use                                                       |
 | `MOODLE_DOCKER_BROWSER`                   | no        | firefox, chrome,  firefox:&lt;tag&gt;, chrome:&lt;tag&gt; | firefox:4       | The browser to run Behat against. Supports a colon notation to specify a specific Selenium docker image version to use. e.g. firefox:2.53.1 can be used to run with older versions of Moodle (<3.5)              |
 | `MOODLE_DOCKER_PHPUNIT_EXTERNAL_SERVICES` | no        | any value                             | not set       | If set, dependencies for memcached, redis, solr, and openldap are added      |

db.pgsql.yml

@@ -3,7 +3,7 @@ services:
     environment:
       MOODLE_DOCKER_DBTYPE: pgsql
   db:
-    image: postgres:${MOODLE_DOCKER_DB_VERSION:-14}
+    image: postgres:${MOODLE_DOCKER_DB_VERSION:-15}
     environment:
       POSTGRES_USER: moodle
       POSTGRES_PASSWORD: "m@0dl3ing"