Change build environment from xilinx-ise to ubuntu-20.04

.github/workflows/build-deb.yml

@@ -10,7 +10,7 @@ on:
 
 jobs:
   build:
-    runs-on: xilinx-ise
+    runs-on: ubuntu-20.04
 
     steps:
       - name: ⚙️ Prepare Environment Variables