Update vendor (#1414)

vendor/github.com/mitchellh/mapstructure/CHANGELOG.md

@@ -1,43 +1,3 @@
-## 1.3.3
-
-* Decoding maps from maps creates a settable value for decode hooks [GH-203]
-
-## 1.3.2
-
-* Decode into interface type with a struct value is supported [GH-187]
-
-## 1.3.1
-
-* Squash should only squash embedded structs. [GH-194]
-
-## 1.3.0
-
-* Added `",omitempty"` support. This will ignore zero values in the source
-  structure when encoding. [GH-145]
-
-## 1.2.3
-
-* Fix duplicate entries in Keys list with pointer values. [GH-185]
-
-## 1.2.2
-
-* Do not add unsettable (unexported) values to the unused metadata key
-  or "remain" value. [GH-150]
-
-## 1.2.1
-
-* Go modules checksum mismatch fix
-
-## 1.2.0
-
-* Added support to capture unused values in a field using the `",remain"` value
-  in the mapstructure tag. There is an example to showcase usage.
-* Added `DecoderConfig` option to always squash embedded structs
-* `json.Number` can decode into `uint` types
-* Empty slices are preserved and not replaced with nil slices
-* Fix panic that can occur in when decoding a map into a nil slice of structs
-* Improved package documentation for godoc
-
 ## 1.1.2
 
 * Fix error when decode hook decodes interface implementation into interface