Allow the names of Secure Files in the download step to be parameterised.

[Burnsy2023]

Required Information

Question, Bug, or Feature?
Type: Feature

Enter Task Name: Download Secure File
https://github.com/Microsoft/azure-pipelines-tasks/tree/master/Tasks/DownloadSecureFileV1

Issue Description

A the moment, the secure file download step only allows you to select a file from a list when using the GUI to create a release pipeline. We have several files that we'd like to parameterise within this step so that the right file is used for a particular deployment. All we'd like to do is put a variable in the 'secure file' field rather than have it only as a drop down selection.

This would be less of a problem when yaml releases arrives, but in the interim, this hopefully small change would be really useful.

[sphanley]

This appears to be a duplicate of #6885, which has quite a bit of discussion.

[github-actions]

This issue is stale because it has been open for 180 days with no activity. Remove the stale label or comment on the issue otherwise this will be closed in 5 days