ci: remove foxy - EOL

Signed-off-by: Bart Jimenez Vera <bjv@capra.ooo>

Author: bjv-capra

.github/workflows/ci.yml

@@ -15,8 +15,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - ros_distribution: "foxy"
-            os: "ubuntu-20.04"
           - ros_distribution: "humble"
             os: "ubuntu-22.04"
           - ros_distribution: "rolling"