z_tilt: return done when reties is 0 (#6766)

Signed-off-by: Chris Krause <krautech3d@gmail.com>

klippy/extras/z_tilt.py

@@ -108,7 +108,7 @@ def check_increase(self, error):
         return self.increasing > 1
     def check_retry(self, z_positions):
         if self.max_retries == 0:
-            return
+            return "done"
         error = round(max(z_positions) - min(z_positions),6)
         self.gcode.respond_info(
             "Retries: %d/%d %s: %0.6f tolerance: %0.6f" % (