[dotnet] Add screenshot support for EventFiringWebElement

[TroyWalshProf]

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Description

Add support for taking element screenshot when the underlying web element is a EventFiringWebElement.

Motivation and Context

Fixes #9256

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[CLAassistant]

All committers have signed the CLA.

[jimevans]

@TroyWalshProf Have you signed the CLA? I'd like to merge this, but can't until that's done.

[TroyWalshProf]

@jimevans - Forgot to run the recheck, CLA is signed.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[diemol]

Meging this as @jimevans said above.