ci: auto merge main into the feature branch [skip ci]

[yshyn-iohk]

Description:

• auto merge the main branch into the a feature brach when a pull request is labeled with autoupdate. The idea of this improvement is to optimize the work of the engineers: engineer shouldn't keep an eye on the PR and press "Update..." button after each successful merge of another PR into the main branch. The bot will do this work for you.

Checklist:

• My PR follows the contribution guidelines of this project
• My PR is free of third-party dependencies that don't comply with the Allowlist
• I have commented my code, particularly in hard-to-understand areas
• 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 checked the PR title to follow the conventional commit specification