fix matrix

Author: ImreSamu

.github/workflows/buildx.yml

@@ -35,15 +35,15 @@ jobs:
         # succesful tests matrix:
         platforms: ['linux/arm64','linux/arm/v7','linux/arm/v6','linux/386','linux/ppc64le']
         postgres: ['15beta4']
-        postgis: ['3.2']
+        postgis: ['3.3']
         variant: [alpine]
         include:
           - postgres: '15beta4'
-            postgis: '3.2'
+            postgis: '3.3'
             variant: 'default'
             platforms: 'linux/arm64'
           - postgres: '15beta4'
-            postgis: '3.2'
+            postgis: '3.3'
             variant: 'default'
             platforms: 'linux/ppc64le'