8308114: Bump minimum version of macOS for x64 to 11.0 (matching aarch64)

Reviewed-by: angorya, jvos

Author: kevinrushforth

buildSrc/mac.gradle

@@ -55,8 +55,7 @@ def defaultSdkPath = "/Applications/Xcode.app/Contents/Developer/Platforms/MacOS
 
 // Set the minimum API version that we require (developers do not need to override this)
 // Note that this is not necessarily the same as the preferred SDK version
-def isAarch64 = TARGET_ARCH == "aarch64" || TARGET_ARCH == "arm64";
-def macOSMinVersion = isAarch64 ? "11.0" : "10.12";
+def macOSMinVersion = "11.0";
 defineProperty("MACOSX_MIN_VERSION", macOSMinVersion);
 
 def macOSMinVersionArr = macOSMinVersion.split("\\.")