chore: create issue template & workflow to automatically open issue for browser testing dependencies updates (Selenium / Playwright)

[DeagleGross]

The idea is to simplify the process of updating browser testing dependencies. Today engineers do it manually by instructions once per month.

The process I am proposing is:

1. There is an issue template with all instructions, so that Copilot can pick this up (even if all automation fails)
2. There is a workflow which runs on the first day of month, and it opens an issue with the same body as in the issue template (unfortunately, there is no way to share them in single file, or i did not find it). Workflow should open an issue and automatically assign copilot to it as per gh issue create docs.

Open questions:

1. i was testing it in a fork, and flow works without --assignee @copilot.
2. with --assignee @copilot it does not work with error "GraphQL: Could not resolve to a User with the login of '@copilot'. (u000)". I suppose that happens in fork only, and it should work in dotnet/aspnetcore repo
3. should we also add a ping of build-ops / Will?

[Copilot]

Pull Request Overview

This PR creates automation infrastructure for monthly browser testing dependency updates by introducing an issue template and automated workflow. The goal is to streamline the previously manual process of updating Selenium and Playwright dependencies that engineers performed monthly.

• Adds GitHub issue template with detailed instructions for updating browser testing dependencies
• Creates scheduled workflow that automatically opens issues on the first day of each month
• Provides both automated and manual trigger options for the dependency update process

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
.github/workflows/browsertesting-open-issue.yml	Monthly scheduled workflow to automatically create dependency update issues
.github/ISSUE_TEMPLATE/70_browsertesting_update_body.md	Template content used by the automated workflow for issue creation
.github/ISSUE_TEMPLATE/70_browsertesting_update.yml	Manual issue template with form fields for browser testing dependency updates

Comments suppressed due to low confidence (1)

.github/ISSUE_TEMPLATE/70_browsertesting_update.yml:1

• The template name 'Request Dep Updates' is too generic and abbreviated. It should be more descriptive like 'Browser Testing Dependencies Update Request' to clearly indicate what type of dependencies are being updated.

name: "Request Dep Updates" 

[wtgodbe]

I think this is good, but we should add to the .md that @dotnet/aspnet-build should be pinged for review on the PR

[sebastienros]

I quickly looked for an action that would allow to write the same prompt as in the issue template but didn't find anything. It seems weird that there isn't a copilot chat GH action that would do it natively so we can skip the issue creation (noise).

Nevertheless it looks very cool!