add check for linux test product name

Author: kostiakoval

Tests/Functional/TestMiscellaneous.swift

@@ -346,8 +346,14 @@ class MiscellaneousTestCase: XCTestCase {
     func testModuleWithTests() {
         fixture(name: "SwiftTesting/SingleTarget", file: #file, line: #line) { prefix in
             XCTAssertBuilds(prefix)
-            XCTAssertDirectoryExists(prefix, ".build", "debug", "Package.xctest")
             XCTAssertFileExists(prefix, ".build", "debug", "Foo.swiftmodule")
+
+            #if os(OSX)
+                XCTAssertDirectoryExists(prefix, ".build", "debug", "Package.xctest")
+            #else
+                XCTAssertDirectoryExists(prefix, ".build", "debug", "test-Package")
+            #endif
+
         }
     }
 }