Update readme.md on quefrency (#12276)

* Update readme.md on quefrency

Fix incorrect flashing instructions

* Update keyboards/keebio/quefrency/readme.md

keyboards/keebio/quefrency/readme.md

@@ -13,7 +13,7 @@ Make example for this keyboard (after setting up your build environment):
 
 Example of flashing this keyboard:
 
-    make keebio/quefrency/rev3:default:avrdude
+    make keebio/quefrency/rev3:default:flash
 
 Handedness detection is already hardwired onto the PCB, so no need to deal with `EE_HANDS` or flashing .eep files.