fix: Update Ubuntu runner version

Author: ThePythonator

.github/workflows/build.yml

@@ -24,12 +24,12 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: ubuntu-20.04
+          - os: ubuntu-latest
             name: Linux
             release-suffix: LIN64
             can-fail: false
 
-          - os: ubuntu-20.04
+          - os: ubuntu-latest
             name: Emscripten
             release-suffix: WEB
             cmake-prefix: emcmake