MM-23574: Remove Segment. (#14712)

* MM-23574: Eliminate Segment.

* Update dependencies.

* Fix review suggestions.

vendor/modules.txt

@@ -403,9 +403,6 @@ github.com/rwcarlsen/goexif/exif
 github.com/rwcarlsen/goexif/tiff
 # github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529
 github.com/sean-/seed
-# github.com/segmentio/analytics-go v3.1.0+incompatible
-## explicit
-github.com/segmentio/analytics-go
 # github.com/segmentio/backo-go v0.0.0-20200129164019-23eae7c10bd3
 ## explicit
 github.com/segmentio/backo-go