Add Windows partition existence test for File class

test/cases/io/FileTest.cpp

@@ -160,9 +160,15 @@ namespace
   {
     File file{this->fileLocation};
     File directory{TestHelper::getResourcesFolderLocation()};
+#ifdef _WIN32
+    File cPartition{"C:"};
+#endif
 
     ASSERT_TRUE(file.exists());
     ASSERT_TRUE(directory.exists());
+#ifdef _WIN32
+    ASSERT_TRUE(cPartition.exists());
+#endif
   }
 
   TEST_F(FileTest, exists_does_not_exist)