ci: Remove pushing to main as part of the release process

[rmi22186]

Background

Previously we pushed to master and main due us assuming we'd move from master to main at some point in the future. master and main in this scenario are both v2 of the web sdk. We've decided we'll make main v3, and so due to some experimentation on this branch causing the commit history to change, this step fails. It is an artifact of the past.

What Has Changed

Remove pushing to main from master.

Screenshots/Video

• {Include any screenshots or video demonstrating the new feature or fix, if applicable}

Checklist

• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.
• I have added tests that prove my fix is effective or that my feature works.
• I have tested this locally.

Additional Notes

• {Any additional information or context relevant to this PR}

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cursor]

PR Summary

Low Risk
Workflow-only change to which git branches receive automated pushes; no product code or deployment logic beyond branch synchronization.

Overview
Staging release branch sync no longer mirrors release commits to main. After checkout of staging, the workflow still pushes HEAD to development, master, and the three release-order-* branches, but the duplicate git push origin HEAD:main is gone and the step is labeled only for master.

This aligns with treating main as v3 while master stays v2, so a forced sync to main was failing when histories diverged. No application or SDK runtime code changes—only .github/workflows/staging-step-3.yml.

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