Merge pull request cncf-tags#274 from klihub/fixes/workflow/use-ubuntu-latest

.github: cross-build binaries on ubuntu-latest.

Author: elezar

.github/workflows/sanity.yml

@@ -49,7 +49,7 @@ jobs:
   # Make sure binaries compile on multiple platforms.
   crossbuild:
     name: "Build / Crossbuild Binaries"
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix: