add 1.9, 1.10, 1.11 to CI, and rm 1.4 on macOS (#28)

For 1.4 on macOS, the `Run julia-actions/setup-julia@v2` action fails consistently.
Cf. #28 (comment)
for details.

---------

Co-authored-by: Rafael Fourquet <[email protected]>

Author: ericphanson

.github/workflows/CI.yml

@@ -31,6 +31,9 @@ jobs:
           - "1.6"
           - "1.7"
           - "1.8"
+          - "1.9"
+          - "1.10"
+          - "1.11"
           - "1"    # latest release
           - "nightly"
         os:
@@ -43,6 +46,8 @@ jobs:
         exclude:
           - os: macOS-latest
             arch: x86
+          - os: macOS-latest
+            version: "1.4" # consistently fails with: "Library not loaded: @rpath/libc++.1.dylib"
     steps:
       - uses: actions/checkout@v5
       - uses: julia-actions/setup-julia@v2