Set macOS deployment target to 11.0. (#132)

Samples/Swift/DaysUntilBirthday/DaysUntilBirthday.xcodeproj/project.pbxproj

@@ -542,7 +542,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 12.0;
+				MACOSX_DEPLOYMENT_TARGET = 11.0;
 				MARKETING_VERSION = 1.0;
 				PRODUCT_BUNDLE_IDENTIFIER = Google.DaysUntilBirthdayOnMac;
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -571,7 +571,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 12.0;
+				MACOSX_DEPLOYMENT_TARGET = 11.0;
 				MARKETING_VERSION = 1.0;
 				PRODUCT_BUNDLE_IDENTIFIER = Google.DaysUntilBirthdayOnMac;
 				PRODUCT_NAME = "$(TARGET_NAME)";

Samples/Swift/DaysUntilBirthday/DaysUntilBirthdayForPod.xcodeproj/project.pbxproj

@@ -633,7 +633,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 12.0;
+				MACOSX_DEPLOYMENT_TARGET = 11.0;
 				MARKETING_VERSION = 1.0;
 				PRODUCT_BUNDLE_IDENTIFIER = Google.DaysUntilBirthdayOnMac;
 				PRODUCT_NAME = "$(TARGET_NAME)";
@@ -663,7 +663,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 12.0;
+				MACOSX_DEPLOYMENT_TARGET = 11.0;
 				MARKETING_VERSION = 1.0;
 				PRODUCT_BUNDLE_IDENTIFIER = Google.DaysUntilBirthdayOnMac;
 				PRODUCT_NAME = "$(TARGET_NAME)";