FIX: missing dup on blocks

[rogercampos]

The dup of the blocks argument was removed on the last refactor of the route_set, but it was necessary. On the other hand, defaults doesn't need a dup since this is already done inside ::ActionDispatch::Routing::Mapper::Mapping.build.

The new test showcases the bug (404 response) with the previous code.

[coveralls]

Coverage increased (+0.0004%) to 99.314% when pulling 1d8db83 on rogercampos:fix/dup into a5d9097 on enriclluelles:master.

[tagliala]

@rogercampos thanks for this PR

I need just two things:

1. Check that the dup is done in each supported version of Rails
2. I need to upgrade contributing guidelines, but please change your commit message to

Fix missing dup on blocks

The dup of the `blocks` argument was removed on the last refactor of the
route_set, but it was necessary. On the other hand, `defaults` doesn't need a
dup since this is already done inside
`::ActionDispatch::Routing::Mapper::Mapping.build`.

The new test showcases the bug (404 response) with the previous code.

Ref: https://chris.beams.io/posts/git-commit/

[gadimbaylisahil]

konto

[rogercampos]

thx!

[rogercampos]

@tagliala done, I checked rails versions 5-0-stable, 5-1, 5-2 and 6-0, they all dup the defaults