[Xcode] Remove file reference that not exist

Base32.xcodeproj/project.pbxproj

@@ -30,7 +30,6 @@
 /* End PBXContainerItemProxy section */
 
 /* Begin PBXFileReference section */
-		6C1C19C51FEEA37600371B6F /* Package@swift-4.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "Package@swift-4.swift"; sourceTree = "<group>"; };
 		6C9233FE1E5307C2003ABE13 /* LinuxMain.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = LinuxMain.swift; path = Tests/LinuxMain.swift; sourceTree = "<group>"; };
 		6CDCD8721D98BE7800A65866 /* README.md */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };
 		6CDCD8731D98BE7800A65866 /* LICENSE */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = LICENSE; sourceTree = "<group>"; };
@@ -91,7 +90,6 @@
 				6CDCD8721D98BE7800A65866 /* README.md */,
 				6CDCD8731D98BE7800A65866 /* LICENSE */,
 				__PBXFileRef_Package.swift /* Package.swift */,
-				6C1C19C51FEEA37600371B6F /* Package@swift-4.swift */,
 				"_____Configs_" /* Configs */,
 				"_____Sources_" /* Sources */,
 				"_______Tests_" /* Tests */,