Update macOS Intel runner

macos-13 no longer there.

Author: ChrisBarker-NOAA

.github/workflows/conda_test.yml

@@ -9,7 +9,7 @@ jobs:
         fail-fast: false
         matrix:
             # macos-13 to get Intel
-            os: ["ubuntu-latest", "windows-latest", "macos-13", "macos-latest"]
+            os: ["ubuntu-latest", "windows-latest", "macos-15-intel", "macos-latest"]
             pyver: ["3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v6