Use available macOS versions on GAH.

Author: grafikrobot

.github/workflows/ci.yml

@@ -143,15 +143,15 @@ jobs:
             container: ubuntu:23.10
             os: ubuntu-latest
             install: clang-17
-          - toolset: clang
-            cxxstd: "11,14,17,2a"
-            os: macos-11
-          - toolset: clang
-            cxxstd: "11,14,17,20,2b"
-            os: macos-12
           - toolset: clang
             cxxstd: "11,14,17,20,2b"
             os: macos-13
+          - toolset: clang
+            cxxstd: "11,14,17,20,23"
+            os: macos-14
+          - toolset: clang
+            cxxstd: "11,14,17,20,23"
+            os: macos-15
 
     runs-on: ${{matrix.os}}
     container: ${{matrix.container}}
@@ -273,9 +273,9 @@ jobs:
         include:
           - os: ubuntu-20.04
           - os: ubuntu-22.04
-          - os: macos-11
-          - os: macos-12
           - os: macos-13
+          - os: macos-14
+          - os: macos-15
 
     runs-on: ${{matrix.os}}
 
@@ -321,9 +321,9 @@ jobs:
         include:
           - os: ubuntu-20.04
           - os: ubuntu-22.04
-          - os: macos-11
-          - os: macos-12
           - os: macos-13
+          - os: macos-14
+          - os: macos-15
 
     runs-on: ${{matrix.os}}
 
@@ -379,9 +379,9 @@ jobs:
         include:
           - os: ubuntu-20.04
           - os: ubuntu-22.04
-          - os: macos-11
-          - os: macos-12
           - os: macos-13
+          - os: macos-14
+          - os: macos-15
 
     runs-on: ${{matrix.os}}