Fix GitHub Actions version tags

Update julia-actions/julia-buildpkg and julia-actions/julia-runtest from v1 to v2

Author: ChrisRackauckas

.github/workflows/ci.yml

@@ -30,8 +30,8 @@ jobs:
             ${{ runner.os }}-test-${{ env.cache-name }}-
             ${{ runner.os }}-test-
             ${{ runner.os }}-
-      - uses: julia-actions/julia-buildpkg@v1
-      - uses: julia-actions/julia-runtest@v1
+      - uses: julia-actions/julia-buildpkg@v2
+      - uses: julia-actions/julia-runtest@v2
         env:
           GROUP: ${{ matrix.group }}
       - uses: julia-actions/julia-processcoverage@v1