Update dotnet releases index url

[Varorbc]

Task name: DotNetCoreInstaller、UseDotNet

Description: Update dotnet releases index url

Documentation changes required: N

Added unit tests: N

Attached related issue: N

Checklist:

• Task version was bumped - please check instruction how to do it
• Checked that applied changes work as expected

[JamieMagee]

Related: dotnet/core#9671

[Varorbc]

@merlynomsft @tarunramsinghani @DergachevE Can you help take a look? And give me some advice, this issue has been bothering me for a long time, I hope it can be merged as soon as possible.

[DergachevE]

@Varorbc thanks for your contribution.
We have already this PR 20752 merged to updated releases URLs.

Also as I can see that you didn't bump the task version

[Varorbc]

@DergachevE That pull request only updated the download url, not the index url. Also, could you let me know which version number I should update to?

[Varorbc]

@DergachevE I've bumped the task version. Could you take another look?

[tarunramsinghani]

Thanks for the contribution. Merging.

[Varorbc]

@tarunramsinghani Can't pull requests be merged yet? What else do I need to do?

[tarunramsinghani]

/azp run

[azure-pipelines]

Azure Pipelines could not run because the pipeline triggers exclude this branch/path.

[tarunramsinghani]

@Varorbc, can you please raise a PR from this repo instead of forked repo to make sure the checks are run before merging.

[Varorbc]

I'm really puzzled about why I need to create a branch in this repository. Do I even have the permissions to create a branch here? Isn't the usual process for creating a pull request to first fork the repository, then create and work on a branch in my own fork before submitting changes?

[Varorbc]

@tarunramsinghani Could you tell me how to do it step by step?

[Varorbc]

/azp run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 20748 in repo microsoft/azure-pipelines-tasks

[tarunramsinghani]

@Varorbc I'll get back with instructions soon.

[tarunramsinghani]

Meanwhile, I can cherrypick these changes and raise a PR to make sure that changes are merged.