SwiftSample app: solve XCode config warnings

src/objective-c/examples/SwiftSample/Info.plist

@@ -7,7 +7,7 @@
 	<key>CFBundleExecutable</key>
 	<string>$(EXECUTABLE_NAME)</string>
 	<key>CFBundleIdentifier</key>
-	<string>io.grpc.$(PRODUCT_NAME:rfc1034identifier)</string>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
 	<key>CFBundleInfoDictionaryVersion</key>
 	<string>6.0</string>
 	<key>CFBundleName</key>

src/objective-c/examples/SwiftSample/SwiftSample.xcodeproj/project.pbxproj

@@ -254,6 +254,7 @@
 				COPY_PHASE_STRIP = NO;
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_TESTABILITY = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_DYNAMIC_NO_PIC = NO;
 				GCC_NO_COMMON_BLOCKS = YES;
@@ -323,6 +324,7 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				INFOPLIST_FILE = Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
+				PRODUCT_BUNDLE_IDENTIFIER = "io.grpc.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "";
 				USER_HEADER_SEARCH_PATHS = "";
@@ -336,6 +338,7 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				INFOPLIST_FILE = Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
+				PRODUCT_BUNDLE_IDENTIFIER = "io.grpc.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_OBJC_BRIDGING_HEADER = "";
 				USER_HEADER_SEARCH_PATHS = "";