[SpecFixtures] Touch the sample projects with Xcode

Xcode insists on these changes.

spec/fixtures/SampleProject/Sample Lib/Sample Lib.xcodeproj/project.pbxproj

@@ -235,6 +235,7 @@
 				51E94E1F164472090035348C /* Release */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 /* End XCConfigurationList section */
 	};

spec/fixtures/SampleProject/SampleProject.xcodeproj/project.pbxproj

@@ -553,6 +553,7 @@
 				51D6A8AF16C445B800E174E1 /* App Store */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 		A346496714F9BE990080D870 /* Build configuration list for PBXProject "SampleProject" */ = {
 			isa = XCConfigurationList;