docs: fix supported versions (electron#32563)

VerteDinde · web-flow · commit d8ad2afcad2e · 2022-01-20T13:07:23.000-08:00
diff --git a/docs/tutorial/support.md b/docs/tutorial/support.md
@@ -73,7 +73,7 @@ until the maintainers feel the maintenance burden is too high to continue doing
 * 16.x.y
 * 15.x.y
 * 14.x.y
-* 13
+* 13.x.y
 
 ### End-of-life
 
