[notes] Add support for multiple authors

[vchrombie]

This PR adds code to support export of multiple authors from the changelog entry.

Resolves #49

[vchrombie]

@sduenas please review when you have time.
Thanks.

[sduenas]

@vchrombie I have this error when running your patch

Traceback (most recent call last):
  File "/home/sduenas/.local/bin/notes", line 8, in <module>
    sys.exit(notes())
  File "/usr/lib/python3/dist-packages/click/core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/core.py", line 782, in main
    rv = self.invoke(ctx)
  File "/usr/lib/python3/dist-packages/click/core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/lib/python3/dist-packages/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/home/sduenas/.local/lib/python3.9/site-packages/release_tools/notes.py", line 108, in notes
    au_content = compose_author_content(project, entry_list)
  File "/home/sduenas/.local/lib/python3.9/site-packages/release_tools/notes.py", line 154, in compose_author_content
    content = composer.compose(project, entries)
  File "/home/sduenas/.local/lib/python3.9/site-packages/release_tools/notes.py", line 358, in compose
    content += author + "\n"
TypeError: can only concatenate list (not "str") to list

This is the input that I use:

---
title: Notes command supports multiple authors in changelog entries
category: added
author:
    - John Smith <jsmith@example.com>
    - John Doe <jdoe@example.com>
issue: 49
notes: >
    The notes command supports exporting of multiple authors
    from the changelog entries. You can add more than one
    author to the changelog entry by defining them as
    ```
    author:
        - John Smith <jsmith@example.com>
        - John Doe <jdoe@example.com>
    ```

[vchrombie]

Hi @sduenas

@vchrombie I have this error when running your patch

This is the same error when you try to generate notes (with --authors) without this feature.

This is the input that I use:

I used the same and it worked fine for me

p0tt3r@wand ~/dev/release-tools                             
(.venv) >🔮$ cat releases/unreleased/notes-command-supports-multiple-authors-in-changelog-entries.yml
---
title: Notes command supports multiple authors in changelog entries
category: added
author: 
    - John Smith <jsmith@example.com>
    - John Doe <jdoe@example.com>
issue: 49
notes: >
    The notes command supports exporting of multiple authors
    from the changelog entries. You can add more than one
    author to the changelog entry by defining them as
    ```
    author: 
        - John Smith <jsmith@example.com>
        - John Doe <jdoe@example.com>
    ```

p0tt3r@wand ~/dev/release-tools                             
(.venv) >🔮$ semverup         [±support-multiple-authors ✓]
0.5.0

p0tt3r@wand ~/dev/release-tools                             
(.venv) >🔮$ notes "release-tools" 0.5.0 --authors
Release notes file '0.5.0.md' created
Authors file updated

p0tt3r@wand ~/dev/release-tools                             
(.venv) >🔮$ cat AUTHORS     [±support-multiple-authors ●●]
Santiago Dueñas <sduenas@bitergia.com>
Venu Vardhan Reddy Tekula <venu@bitergia.com>
Jose Javier Merchante <jjmerchante@bitergia.com>
John Smith <jsmith@example.com>
John Doe <jdoe@example.com>

p0tt3r@wand ~/dev/release-tools                             
(.venv) >🔮$ cat releases/0.5.0.md 
## release-tools 0.5.0 - (2022-06-21)

**New features:**

 * Notes command supports multiple authors in changelog entries (#49)\
   The notes command supports exporting of multiple authors from the
   changelog entries. You can add more than one author to the changelog
   entry by defining them as ``` author:      - John Smith
   <jsmith@example.com>     - John Doe <jdoe@example.com> ```
 * Option `--bump-version` to increase version manually\
   Include `--bump-version=[MAJOR, MINOR, PATCH]` argument to `sermverup`
   command to increase the version number regardless the release notes
   changes.

@jjmerchante, could you also help to test the patch just to have another view?

[sduenas]

The patch looks good to me but we need to improve the tests.

[sduenas]

@vchrombie I have this error when running your patch

This is the same error when you try to generate notes (with --authors) without this feature.

My fault, I was using an older version and not the one from your branch.

[vchrombie]

Hi @sduenas, please have a look at this PR when you have free time.
Thank you so much.

[sduenas]

LGTM

[vchrombie]

Thanks for merging this @sduenas.