Bump to agda-2.8.0

Author: omelkonian

.github/workflows/ci.yml

@@ -13,10 +13,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - uses: omelkonian/setup-agda@v2.2
+      - uses: omelkonian/setup-agda@v2.3
         with:
-          agda-version: 2.7.0.1
-          stdlib-version: 2.2
+          agda-version: 2.8.0
+          stdlib-version: 2.3
           main: standard-library-classes
           deploy: ${{ github.ref == 'refs/heads/master' }}
           token: ${{ secrets.GITHUB_TOKEN }}