Remove empty Swift file for Flipper (facebook#27922)

Summary:
Related to facebook#27426 & facebook#27565.

The wish to not include an empty Swift file to trigger the correct Xcode settings was voiced in facebook#27426 & facebook#27565.

## Changelog

[iOS] [Fixed] - Remove need for Swift file in the user’s project in order to use Flipper
Pull Request resolved: facebook#27922

Test Plan:
An application created with the template, like so:

```bash
react-native init --template=~/Code/React/react-native TestFlipper
```

…will successfully build, launch, and have Flipper connect.

Differential Revision: D19690592

Pulled By: cpojer

fbshipit-source-id: ee696e0d747d6338534b0c2d62029e64ece02cd3

template/ios/HelloWorld.xcodeproj/project.pbxproj

@@ -16,7 +16,6 @@
 		2D02E4BD1E0B4A84006451C7 /* Images.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 13B07FB51A68108700A75B9A /* Images.xcassets */; };
 		2D02E4BF1E0B4AB3006451C7 /* main.m in Sources */ = {isa = PBXBuildFile; fileRef = 13B07FB71A68108700A75B9A /* main.m */; };
 		2DCD954D1E0B4F2C00145EB5 /* HelloWorldTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 00E356F21AD99517003FC87E /* HelloWorldTests.m */; };
-		37E9F8DD2399A8DD00F82F3E /* Swift.swift in Sources */ = {isa = PBXBuildFile; fileRef = 37E9F8DC2399A8DD00F82F3E /* Swift.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -50,7 +49,6 @@
 		13B07FB71A68108700A75B9A /* main.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = main.m; path = HelloWorld/main.m; sourceTree = "<group>"; };
 		2D02E47B1E0B4A5D006451C7 /* HelloWorld-tvOS.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = "HelloWorld-tvOS.app"; sourceTree = BUILT_PRODUCTS_DIR; };
 		2D02E4901E0B4A5D006451C7 /* HelloWorld-tvOSTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = "HelloWorld-tvOSTests.xctest"; sourceTree = BUILT_PRODUCTS_DIR; };
-		37E9F8DC2399A8DD00F82F3E /* Swift.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Swift.swift; sourceTree = "<group>"; };
 		ED297162215061F000B7C4FE /* JavaScriptCore.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = JavaScriptCore.framework; path = System/Library/Frameworks/JavaScriptCore.framework; sourceTree = SDKROOT; };
 		ED2971642150620600B7C4FE /* JavaScriptCore.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = JavaScriptCore.framework; path = Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS12.0.sdk/System/Library/Frameworks/JavaScriptCore.framework; sourceTree = DEVELOPER_DIR; };
 /* End PBXFileReference section */
@@ -137,7 +135,6 @@
 		83CBB9F61A601CBA00E9B192 = {
 			isa = PBXGroup;
 			children = (
-				37E9F8DC2399A8DD00F82F3E /* Swift.swift */,
 				13B07FAE1A68108700A75B9A /* HelloWorld */,
 				832341AE1AAA6A7D00B99B32 /* Libraries */,
 				00E356EF1AD99517003FC87E /* HelloWorldTests */,
@@ -402,7 +399,6 @@
 			buildActionMask = 2147483647;
 			files = (
 				13B07FBC1A68108700A75B9A /* AppDelegate.m in Sources */,
-				37E9F8DD2399A8DD00F82F3E /* Swift.swift in Sources */,
 				13B07FC11A68108700A75B9A /* main.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -455,7 +451,6 @@
 		00E356F61AD99517003FC87E /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				GCC_PREPROCESSOR_DEFINITIONS = (
 					"DEBUG=1",
@@ -478,7 +473,6 @@
 		00E356F71AD99517003FC87E /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				COPY_PHASE_STRIP = NO;
 				INFOPLIST_FILE = HelloWorldTests/Info.plist;
@@ -501,7 +495,6 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
 				CURRENT_PROJECT_VERSION = 1;
-				DEAD_CODE_STRIPPING = NO;
 				INFOPLIST_FILE = HelloWorld/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				OTHER_LDFLAGS = (
@@ -690,6 +683,12 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				LD_RUNPATH_SEARCH_PATHS = "/usr/lib/swift $(inherited)";
+				LIBRARY_SEARCH_PATHS = (
+					"\"$(TOOLCHAIN_DIR)/usr/lib/swift/$(PLATFORM_NAME)\"",
+					"\"$(TOOLCHAIN_DIR)/usr/lib/swift-5.0/$(PLATFORM_NAME)\"",
+					"\"$(inherited)\"",
+				);
 				MTL_ENABLE_DEBUG_INFO = YES;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = iphoneos;
@@ -736,6 +735,12 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				LD_RUNPATH_SEARCH_PATHS = "/usr/lib/swift $(inherited)";
+				LIBRARY_SEARCH_PATHS = (
+					"\"$(TOOLCHAIN_DIR)/usr/lib/swift/$(PLATFORM_NAME)\"",
+					"\"$(TOOLCHAIN_DIR)/usr/lib/swift-5.0/$(PLATFORM_NAME)\"",
+					"\"$(inherited)\"",
+				);
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
 				VALIDATE_PRODUCT = YES;