ci: add minimum GitHub token permissions for workflows

[ashishkurmi]

Description

This PR adds minimum token permissions for the GITHUB_TOKEN in GitHub Actions workflows using secure-workflows.

The GitHub Actions workflow has a GITHUB_TOKEN with write access to multiple scopes. Here is an example of the permissions in one of the workflow runs:
https://github.com/open-mmlab/mmdetection/actions/runs/3095931510/jobs/5010897300#step:1:19

After this change, the scopes will be reduced to the minimum needed for the following workflows:

• build.yml
• build_pat.yml
• deploy.yml
• lint.yml
• stale.yml
• test_mim.yml

Motivation and Context

• This is a security best practice, so if the GITHUB_TOKEN is compromised due to a vulnerability or compromised Action, the damage will be reduced.
• GitHub recommends defining minimum GITHUB_TOKEN permissions.
• The Open Source Security Foundation (OpenSSF) Scorecards also treats not setting token permissions as a high-risk issue. This change will help increase the Scorecard score for this repository.

Signed-off-by: Ashish Kurmi [email protected]

[CLAassistant]

All committers have signed the CLA.

[OpenMMLab-Assistant005]

Hi @boahc077 ！First of all, we want to express our gratitude for your significant PR in the MMDet project. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.

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