Fix triage workflow when the card already exists in project (#63347)

Fix triage workflow when the card already exists in project (#63347)

Summary:
Fixes issues like https://github.com/pytorch/pytorch/runs/3336787242

```
RequestError [HttpError]: Validation Failed: {"resource":"ProjectCard","code":"unprocessable","field":"data","message":"Project already has the associated issue"}
Error: Unhandled error: HttpError: Validation Failed: {"resource":"ProjectCard","code":"unprocessable","field":"data","message":"Project already has the associated issue"}
    at /home/runner/work/_actions/actions/github-script/v2/dist/index.js:7531:23
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
    at async eval (eval at callAsyncFunction (/home/runner/work/_actions/actions/github-script/v2/dist/index.js:7985:56), <anonymous>:63:1)
    at async main (/home/runner/work/_actions/actions/github-script/v2/dist/index.js:8011:20) {
  name: 'HttpError',
  status: 422,

...
```

The card may already exist, thus no need to handle `422` status code. Anything else will re-throw the err.

Pull Request resolved: https://github.com/pytorch/pytorch/pull/63347

Reviewed By: malfet

Differential Revision: D30348529

Pulled By: zhouzhuojie

fbshipit-source-id: 36647837bfccad43ce01eb5dfe6642e685615037