test on 1.6 also (#3966)

* test on 1.6 also

* Update ci.yml

* Update ci.yml

* Update ci.yml

* Update ci.yml

live up to the claimed `[compat]`

* change matrix

* remove ifs

* update include

* split include array

Co-authored-by: Jerry Ling <proton@jling.dev>

.github/workflows/ci.yml

@@ -22,18 +22,23 @@ jobs:
       fail-fast: false
       matrix:
         version:
-          - '1'
+          - '1.5'
+          - '1.6'
           - 'nightly'
         os:
           - ubuntu-latest
-          - windows-latest
-          - macos-latest
         arch:
           - x64
           # - x86
+        include:
+          - version: '1'
+            os: ubuntu-latest
+          - version: '1'
+            os: windows-latest
+          - version: '1'
+            os: macos-latest
 
     steps:
-
       # Setup environment
       - uses: actions/checkout@v2
       - uses: julia-actions/setup-julia@latest