Update build-idl.yaml (#724)

Use ubuntu-latest per actions/runner-images#11101

Fixes #721 (maybe)

Author: npm1

.github/workflows/build-idl.yaml

@@ -6,7 +6,7 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
 
     steps:
       - name: Checkout repository