Update tests.yaml (#725)

Author: jGaboardi

.github/workflows/tests.yaml

@@ -36,9 +36,9 @@ jobs:
           - ci/envs/313-dev.yaml
         include:
           - environment-file: ci/envs/313-latest.yaml
-            os: macos-13  # Intel
+            os: macos-15-intel  # Intel
           - environment-file: ci/envs/313-latest.yaml
-            os: macos-14  # Apple Silicon
+            os: macos-latest  # Apple Silicon
           - environment-file: ci/envs/313-latest.yaml
             os: windows-latest
           - environment-file: ci/envs/313-min.yaml