Fix help text for limits hit metric

Signed-off-by: Douglas Camata <159076+douglascamata@users.noreply.github.com>

pkg/receive/limiter.go

@@ -32,7 +32,7 @@ func newRequestLimiter(sizeBytesLimit, seriesLimit, samplesLimit int64, reg prom
 				Namespace:  "thanos",
 				Subsystem:  "receive",
 				Name:       "write_limits_hit",
-				Help:       "The number of times a request was refused due to a remote write limit.",
+				Help:       "Summary of how much beyond the limit a refused remote write request was.",
 				Objectives: map[float64]float64{0.50: 0.1, 0.95: 0.1, 0.99: 0.001},
 			}, []string{"tenant", "limit"},
 		),