…extProvider (xepozz)

This PR was submitted for the master branch but it was merged into the 4.3 branch instead.

Discussion
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[VarDumper] Fix "Undefined index: argv" when using CliContextProvider

| Q             | A
| ------------- | ---
| Branch?       | 4.1, 4.2, 4.3, 4.4 or 5.0<!-- see below -->
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix #35084
| License       | MIT
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Commits
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340bb14 Fixed #35084