Context access might be invalid, on Forked Repos with Secerts

**Describe the bug**
If working on a forked repo with actions with secrets and environment variables, the plugin will always give this warning while using any of them in the workflows.
Would suggest, either disabling this specific warning if the repo is forked or adding the option to point to the forked repo!

**Extension Version**
v0.26.2

Start by reproducing the warning in VS Code extension v0.26.2 using a workflow in a forked repository that references secrets or environment variables. Trace how the extension validates context access for forked workflows; done means the warning is no longer incorrectly shown or the reported fork-repository configuration is supported.

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