Bump 1.8 CI to beta3.

Author: maleadt

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        version: ['1.6', '1.7', '^1.8.0-beta1', 'nightly']
+        version: ['1.6', '1.7', '^1.8.0-beta3', 'nightly']
         os: [ubuntu-latest, macOS-latest, windows-latest]
         arch: [x64]
         assertions: [false]