Fix Template Specification API Auth Object formatting

[tom139]

Description:

In the SAM Template Specification (versions/2016-10-31.md) the paragraph about the API Auth Object is badly formatted.

Steps to reproduce the issue:

1. Go to the API Auth Object paragraph of versions/2016-10-31.md (AKA SAM Template Specification)

Observed result:

The YAML for the Authorizers section is badly formatted (because the ```yaml block is opened twice).

Expected result:

Better formatting.

[tom139]

I will submit a PR in a few minutes, addressing this issue.

[keetonian]

Released!