Update CMAKE_OSX_DEPLOYMENT_TARGET to 15.0 (#46)

As GitHub upgrades its macOS machine to 15.0, we update this var

Author: haochengxia

pyproject.toml

@@ -66,7 +66,7 @@ build-dir = "build"
 [tool.scikit-build.cmake]
 build-type = "Release"
 args = ["-G", "Ninja"]
-define = { CMAKE_OSX_DEPLOYMENT_TARGET = "14.0" }
+define = { CMAKE_OSX_DEPLOYMENT_TARGET = "15.0" }
 version = ">=3.15"
 source-dir = "."