Updated gha

Author: zajo

.github/workflows/ci.yml

@@ -175,15 +175,15 @@ jobs:
             container: ubuntu:25.04
             os: ubuntu-latest
             install: clang-20
-          - toolset: clang
-            cxxstd: "11,14,17,20,2b"
-            os: macos-13
           - toolset: clang
             cxxstd: "11,14,17,20,2b"
             os: macos-14
           - toolset: clang
             cxxstd: "11,14,17,20,2b"
             os: macos-15
+          - toolset: clang
+            cxxstd: "11,14,17,20,2b"
+            os: macos-26
 
     runs-on: ${{matrix.os}}