WIP: simplified matrix

Author: lrineau

.github/workflows/matrix.json

@@ -1,14 +1,14 @@
 {
     "cgal_branch": [
         "v6.1",
-        "6.1.x-branch",
-        "main"
+        // "6.1.x-branch",
+        // "main"
     ],
     "python-version": [
-        "3.10",
-        "3.11",
-        "3.12",
-        "3.13",
+        // "3.10",
+        // "3.11",
+        // "3.12",
+        // "3.13",
         "3.14"
     ],
     "os": [