Revert change

Author: pvzig

Sources/SKRTMAPI/SKRTMAPI.swift

@@ -21,7 +21,9 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if os(Linux)
 import Dispatch
+#endif
 import Foundation
 import SKWebAPI
 @_exported import SKCore