ignore nightly in CI testing

Author: franckgaga

.github/workflows/CI.yml

@@ -14,6 +14,7 @@ jobs:
   test:
     name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }} - ${{ github.event_name }}
     runs-on: ${{ matrix.os }}
+    continue-on-error: ${{ matrix.version == 'nightly' }}
     strategy:
       fail-fast: false
       matrix: