README: Fix typo (#92)

overheard => overhead

README.md

@@ -39,11 +39,11 @@ func main() {
 }
 ```
 
-## FAQ: 
+## FAQ:
 - What's the major diff v.s. https://pkg.go.dev/golang.org/x/time/rate? (based on #77)
 
-  This ratelimiter was meant to have a (1) simple API and (2) minimal overheard. For more complex use-cases [x/time/rate] is a great choice.  See [here][redit] for historical context, and [here][bench] for benchmarks (from 2016).
-  
+  This ratelimiter was meant to have a (1) simple API and (2) minimal overhead. For more complex use-cases [x/time/rate] is a great choice.  See [here][redit] for historical context, and [here][bench] for benchmarks (from 2016).
+
 - Why does example_test.go fail when I run it locally on Windows? (based on #80)
 
   Windows has some known issues with timers precision. See golang/go#44343. We don't expect to work around it.