Enable dynamically ciflow/slow so that we can run GHA slow tests on PR (#61987)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/61987
This PR enables us to run slow GHA tests on PR.
Steps to do (~may only take effect after this PR is merged~ works on this PR)
- Add label `ciflow/slow`
- Assign/unassign pytorchbot
- The job should be running .github/workflows/pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7.yml
The above steps are manual, and after probot can do the dispatch work, the ciflow will be automated.
Related meta RFC issue: #61888
Test Plan: Imported from OSS
Reviewed By: driazati
Differential Revision: D29832758
Pulled By: zhouzhuojie
fbshipit-source-id: 64d31ef572502e62b80e6b7ac480ffcfa9f4e38b
