[VOL-4290] Voltha go library updates for gRPC migration

Change-Id: I1aa2774beb6b7ed7419bc45aeb53fcae8a8ecda0
diff --git a/vendor/github.com/prometheus/common/expfmt/decode.go b/vendor/github.com/prometheus/common/expfmt/decode.go
index c092723..7657f84 100644
--- a/vendor/github.com/prometheus/common/expfmt/decode.go
+++ b/vendor/github.com/prometheus/common/expfmt/decode.go
@@ -164,7 +164,7 @@
 }
 
 // ExtractSamples builds a slice of samples from the provided metric
-// families. If an error occurrs during sample extraction, it continues to
+// families. If an error occurs during sample extraction, it continues to
 // extract from the remaining metric families. The returned error is the last
 // error that has occurred.
 func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) (model.Vector, error) {