Update README to clarify the scope of issues.

[reasonerjt]

Thank you for contributing to Velero!

Please add a summary of your change

Does your change fix a particular issue?

Fixes #(issue)

Please indicate you've done the following:

• [X] Accepted the DCO. Commits without the DCO will delay acceptance.
• [X] Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• [ ] Updated the corresponding documentation in site/content/docs/main.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 58.58%. Comparing base (5f9c53a) to head (b117963).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #7717 +/- ## ========================================== - Coverage 58.60% 58.58% -0.03% ========================================== Files 343 343 Lines 28593 28593 ========================================== - Hits 16757 16751 -6 - Misses 10418 10423 +5 - Partials 1418 1419 +1 ```

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[weshayutin]

@anshulahuja98 @draghuram @ihcsim @Frank51 WDYT? In an attempt to keep downstream bugs out of upstream velero, we were thinking to link to downstream support in the troubleshooting guide. If you agree and have clearance to add a link perhaps post here.

[anshulahuja98]

@anshulahuja98 @draghuram @ihcsim @Frank51 WDYT? In an attempt to keep downstream bugs out of upstream velero, we were thinking to link to downstream support in the troubleshooting guide. If you agree and have clearance to add a link perhaps post here.

Hi I think overall this makes sense for products which are OSS and using velero (ex. OADP). Where customer is truly aware that velero is the underlying engine and hence they might create issues here. For our product, it is more of a managed solution, we don't expect customers to create any issues on github(we do not mention/ encourage the route) Issues flow through MS Support and eventually reach us, then our engineering team follows up in community as required.

So far no customer of our product has created issues directly, and I don't expect that to change in near future.

Having said that, I don't have anything to add in terms of links for now. We can evaluate in the future again if something changes for us in terms of support.