Bump the macOS deployment target to 10.13 in the Xcode project.

Author: grynspan

XCTest.xcodeproj/project.pbxproj

@@ -513,7 +513,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 12.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				"LD_RUNPATH_SEARCH_PATHS[sdk=macosx*]" = "@executable_path/../Frameworks @loader_path/Frameworks";
-				MACOSX_DEPLOYMENT_TARGET = 10.12;
+				MACOSX_DEPLOYMENT_TARGET = 10.13;
 				"OTHER_LDFLAGS[sdk=macosx*]" = (
 					"-framework",
 					SwiftFoundation,
@@ -538,7 +538,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 12.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				"LD_RUNPATH_SEARCH_PATHS[sdk=macosx*]" = "@executable_path/../Frameworks @loader_path/Frameworks";
-				MACOSX_DEPLOYMENT_TARGET = 10.12;
+				MACOSX_DEPLOYMENT_TARGET = 10.13;
 				"OTHER_LDFLAGS[sdk=macosx*]" = (
 					"-framework",
 					SwiftFoundation,