Add julia 1.8 in CI

Author: Azzaare

.github/workflows/ci.yml

@@ -12,6 +12,7 @@ jobs:
         version:
           - '1.6'
           - '1.7'
+          - "^1.8.0-0"
           - 'nightly'
         os:
           - ubuntu-latest
@@ -58,7 +59,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: julia-actions/setup-julia@v1
         with:
-          version: "1.7"
+          version: "1"
       - run: |
           julia --project=docs -e '
             using Pkg