Fix birmingHack link

LMBishop · LMBishop · commit af15729271f9 · 2025-06-02T18:06:39.000+01:00
diff --git a/README.md b/README.md
@@ -153,7 +153,7 @@ N.B.: The die-cut dimensions include the white border around the graphic. So the
 
 ## birmingHack
 
-See [birminghack/README.md].
+See [birminghack/README.md](birminghack/README.md).
 
 ## Roller Banner
 
