re-establish CI on 1.6

Author: j-fu

.github/workflows/ci.yml

@@ -15,9 +15,9 @@ jobs:
       fail-fast: false
       matrix:
         version:
-          - '1.7' # Replace this with the minimum Julia version that your package supports. E.g. if your package requires Julia 1.5 or higher, change this to '1.5'.
+          - '1.6' # Replace this with the minimum Julia version that your package supports. E.g. if your package requires Julia 1.5 or higher, change this to '1.5'.
           - '1'   # Leave this line unchanged. '1' will automatically expand to the latest stable 1.x release of Julia.
-        #  - 'nightly' # currently fails for LinearSolve
+          - 'nightly' # currently fails for LinearSolve
         os:
           - ubuntu-latest
           - macos-latest

test/Project.toml

@@ -15,4 +15,4 @@ AlgebraicMultigrid = "0.4,0.5"
 IncompleteLU = "^0.2"
 IterativeSolvers = "0.9"
 Pardiso = "^0.5.1"
-Sparspak = "0.2"
+Sparspak = "0.2.1"