Cannot get latest version (v12.2.0)

[filippo-veneri]

Describe the bug
The latest version (v12.2.0 at the moment) is effectivly un-gettable.

To Reproduce
Steps to reproduce the behavior:

1. go get github.com/iris-contrib/swagger/v12@master
   We get the following line in go.mod:
   require github.com/iris-contrib/swagger/v12 v12.2.0-alpha //wrong version

2. go get github.com/iris-contrib/swagger/v12@v12.2.0
   We get this error:
   go: github.com/iris-contrib/swagger@v12.2.0: invalid version: module contains a go.mod file, so module path must match major version ("github.com/iris-contrib/swagger/v12")

Expected behavior
We should get the correct version in go.mod:
require github.com/iris-contrib/swagger/v12 v12.2.0

Desktop (please complete the following information):

• OS: all majior [linux, windows, osx]

iris.Version

• v12.2.1

Additional context
The problem is due to the fact that, in the master branch, the module declaration in go.mod lacks the v12 suffix.

[filippo-veneri]

Duplicate of #16

[diablur]

same problem,
we should change the 'module github.com/iris-contrib/swagger' to 'module github.com/iris-contrib/swagger/v12' in go.mod