go: github.com/pkg/errors upgrade => v0.9.1 (#145)

Author: k-ye

go.mod

@@ -47,7 +47,7 @@ require (
 	github.com/nbutton23/zxcvbn-go v0.0.0-20180912185939-ae427f1e4c1d // indirect
 	github.com/pborman/uuid v1.2.0
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
-	github.com/pkg/errors v0.8.1
+	github.com/pkg/errors v0.9.1
 	github.com/remyoudompheng/bigfft v0.0.0-20190728182440-6a916e37a237 // indirect
 	github.com/rwcarlsen/goexif v0.0.0-20190401172101-9e8deecbddbd // indirect
 	github.com/stretchr/objx v0.2.0 // indirect

go.sum

@@ -195,6 +195,8 @@ github.com/phpdave11/gofpdi v1.0.7 h1:k2oy4yhkQopCK+qW8KjCla0iU2RpDow+QUDmH9DDt4
 github.com/phpdave11/gofpdi v1.0.7/go.mod h1:vBmVV0Do6hSBHC8uKUQ71JGW+ZGQq74llk/7bXwjDoI=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=