infra: macos-13 is deprecated (#89)

* macos-13 is deprecated

* use macos-15-intel

.github/workflows/build.yml

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 11ff562..decc86e 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -116,7 +116,7 @@
   build-macos-x86_64:
     needs: [generate-license]
     name: Mac x86_64
-    runs-on: macos-13
+    runs-on: macos-15-intel
     strategy:
       fail-fast: false
       matrix: