Drop macos-11 runner and support macos-14 instead

Change-Id: Ie2958fa64f8c76ef6cc58af3da62dbc0607ba52a

.github/workflows/macos.yml

diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index e5690c5..89c3534 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -16,9 +16,9 @@
       fail-fast: true
       matrix:
         os:
-          - macos-11
           - macos-12
           - macos-13
+          - macos-14
         build_type:
           - Release
         lib:
@@ -74,7 +74,7 @@
                 -DCMAKE_C_COMPILER_LAUNCHER=$(which ccache) \
                 -DCMAKE_CXX_COMPILER_LAUNCHER=$(which ccache) \
                 -DCMAKE_TOOLCHAIN_FILE=${{github.workspace}}/cmake/iOS.cmake \
-                -DEigen3_DIR=/usr/local/share/eigen3/cmake \
+                -DEigen3_DIR=$(brew --prefix)/share/eigen3/cmake \
                 -DIOS_PLATFORM=OS \
                 -DCMAKE_INSTALL_PREFIX=${{github.workspace}}/install