Added workflow to automaticly update the rollbar.snippet.js

[danielmorell]

Description of the change

Keeping the rollbar.snippet.js file up to date with the rollbar.js package currently requires some copy and paste. It also is often forgotten. This PR creates a simple workflow that will update the JS file to the latest version (or a specific version if spcified), commit the updated file, and create a PR to be reviewed. It allows a one click update process.

Keeping the file up to date is imporant for downstream packages like the WordPress plugin.

Type of change

• Maintenance

Related issues

None

Checklists

Development

• Lint rules pass locally
• The code changed/added as part of this pull request has been covered with tests
• All tests related to the changed code pass in development

Code review

• This pull request has a descriptive title and information useful to a reviewer. There may be a screenshot or screencast attached
• "Ready for review" label attached to the PR and reviewers assigned
• Issue from task tracker has a link to this pull request
• Changes have been reviewed by at least one other engineer