fix(extend): extends multiple named styles (fix #1345)

[fi3ework]

Corresponding issue (if exists):

#1345

What would you like to add/fix?

Now plugin can extend both named and object in the array.

Todo

• Add tests if possible
• Add changelog if users should know about the change
• Add documentation

[kof]

Hey, LGTM, missing docs and changelog and we are good to go

[fi3ework]

Hi @kof, thanks for replying. Should I execute yarn version and bump a patch version? contributing.md did not list how to update changelog independently.

[kof]

@fi3ework no, just add the info where needed in /docs and add the changelog affter --- in changelog.md, like the rest of the file

[fi3ework]

@kof Done, please review again. 😆

[kof]

merged, thank you!

[kof]

released in 10.4.0