Fixes crashes when asyncdispatch.adjustTimeout returns a negative value. (#11231)

lib/pure/selectors.nim

@@ -314,6 +314,14 @@ else:
     key.events = {}
     key.data = empty
 
+  proc verifySelectParams(timeout: int) =
+    # Timeout of -1 means: wait forever
+    # Anything higher is the time to wait in miliseconds.
+    if timeout < -1:
+      raise newException(
+        ValueError, "Cannot select with a negative value, got " & $timeout
+      )
+
   when defined(linux):
     include ioselects/ioselectors_epoll
   elif bsdPlatform: