IBX-10494: Mark PostgreSQL 18 as supported (#2994)

* IBX-10494: Mark PostgreSQL 18 as supported

* Apply suggestions from code review

Co-authored-by: Adrien Dupuis <61695653+adriendupuis@users.noreply.github.com>

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Co-authored-by: Adrien Dupuis <61695653+adriendupuis@users.noreply.github.com>

Author: mnocon

docs/getting_started/requirements.md

@@ -100,16 +100,16 @@ For production setups it's recommended that you use Varnish/Fastly, Redis, NFS/E
 
     - MariaDB 10.11+ or 11.4
     - MySQL 8.4
-    - PostgreSQL 14
+    - PostgreSQL 14 or 18
 
     If you see a "+" next to the product version, it indicates a recommended version or higher within the same major release.
     For example, "1.18+" means any 1.x version equal to or higher than 1.18, but not 2.x.
 
 === "[[= product_name =]] v4.6"
 
     - MariaDB 10.3-10.11+ or 11.4
-    - MySQL 8.0, 8.4
-    - PostgreSQL 14
+    - MySQL 8.0 or 8.4
+    - PostgreSQL 14 or 18
 
     If you see a "+" next to the product version, it indicates a recommended version or higher within the same major release.
     For example, "1.18+" means any 1.x version equal to or higher than 1.18, but not 2.x.