Update docs/dev/style.md

Co-authored-by: Laurențiu Nicola <[email protected]>

Author: matklad

docs/dev/style.md

@@ -246,7 +246,7 @@ impl Ctx {
 
 The difference is that `Ctx` is an impl detail here.
 
-Sometimes a middle ground is acceptable if this can safe some busywork:
+Sometimes a middle ground is acceptable if this can save some busywork:
 
 ```rust
 ThingDoer::do(arg1, arg2);