Fix AutoDiff_Ext tests: use Julia 1.11 instead of latest (1.12)

Author: albertomercurio

.github/workflows/CI.yml

@@ -68,7 +68,7 @@ jobs:
               os: 'ubuntu-latest'
               arch: 'x64'
             group: 'Makie_Ext'
-          - version: '1'
+          - version: '1.11'
             node:
               os: 'ubuntu-latest'
               arch: 'x64'