Update takanome-dev/assign-issue-action to beta

[koppor]

Now, on assignment via the action, the project is also updated. No more action with the "Assigned" label.

Refs takanome-dev/assign-issue-action#247

Can be merged if takanome-dev/assign-issue-action#245 is merged.

I hope that m7kvqbe1/github-action-move-issues#4 will also be implemented soon 😅

Mandatory checks

• I own the copyright of the code submitted and I licence it under the MIT license
• Change in CHANGELOG.md described in a way that is understandable for the average user (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
• Checked documentation: Is the information available and up to date? If not, I created an issue at https://github.com/JabRef/user-documentation/issues or, even better, I submitted a pull request to the documentation repository.

[github-actions]

The build of this PR is available at https://builds.jabref.org/pull/12012/merge.

[koppor]

• Test PR of take action not merged, thus using the branch name
• Test PR of project action available: Add SKIP_IF_NOT_IN_PROJECT flag m7kvqbe1/github-action-move-issues#28

Updated the code, will merge to be able to test.

[github-actions]

The build of this PR is available at https://builds.jabref.org/pull/12012/merge.

[koppor]

Added required field maintainers - takanome-dev/test-gh-actions#2 (comment)

[github-actions]

The build for this PR is no longer available. Please visit https://builds.jabref.org/main/ for the latest build.