Add Pull Request template support for create-pr command

[tonymartmann]

Motivation

Describe here the motivation of the request.

We are using a pull request template to fill the description of the PR automatically when it's created. We'd like the cpr command supports pull request templates.

Acceptance criteria

• Add a parameter to the cpr command to include pull request template in the description of the PR we want to create.

[jorgegarciarey]

Hi @tonymartmann ,

We are developing this feature by adding a new parameter (--from-template) to the create pull request command. The command will look something like this:

gh sherpa create-pr --issue ID --from-template