Add an introduction for ASCornerLayoutSpec in layout2-layoutspec-types.md #trivial

[huang-kun]

Add an introduction for ASCornerLayoutSpec in layout2-layoutspec-types.md

[maicki]

Hey @huang-kun I think this PR was opened accidentally. I will close it. Thanks!

[huang-kun]

@maicki Would you add an introduction for new features in version 2.7? Here

[maicki]

@huang-kun Ah sorry I apologize for closing it. There were merge conflicts in there and the title was not really describing what the PR is about, so I thought it was created accidentally.

I will reopen the PR, can you please remove all of the merge conflicts and squash the branch into one?

Thanks!

[maicki]

Please remove all of the merge conflicts.

[CLAassistant]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
2 out of 3 committers have signed the CLA.

✅ nguyenhuy
✅ huang-kun
❌ huangkun

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[garrettmoon]

@huang-kun would you mind squashing your commits or updating the author on them? A few of them look like they have a non-github author.