Paren-matching kernel launch check without external deps (#60778)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/60778
Matches parens and the opening `<<<` to make a more accurate kernel launch check.
Test Plan:
```
buck test //caffe2/test:kernel_launch_checks
```
Reviewed By: ngimel
Differential Revision: D29401624
fbshipit-source-id: 8649af7c33e67dbb24044af0134b1cea6f2e5dc3
