Drop removed macos-13 runner

Change-Id: I7f37bb2f71324353a45e39d12792edabfb3956b7

.github/workflows/macos.yml

diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index a71c390..eee89ff 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -16,7 +16,6 @@
       fail-fast: true
       matrix:
         os:
-          - macos-13
           - macos-14
           - macos-15
         build_type: