What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespaces from that line:

/kind bug
/kind task
/kind feature

What does this PR do / why do we need it:
Concatenates tensors along one dimension.

Which issue(s) this PR fixes:

Fixes #I48O7Z:【众智】【计算-AICPU开发】Concat

Special notes for your reviewers: