added references to Limiter docs for 0-1 behaviour

Author: Jajanidze

middleware/rate_limiter.go

@@ -170,6 +170,9 @@ type (
 /*
 NewRateLimiterMemoryStore returns an instance of RateLimiterMemoryStore with
 the provided rate (as req/s). The provided rate less than 1 will be treated as zero.
+Also rate between 0 and 1 will be treated as zero.
+for more info check out Limiter docs - https://pkg.go.dev/golang.org/x/time/rate#Limit.
+
 Burst and ExpiresIn will be set to default values.
 
 Example (with 20 requests/sec):