fix: mitigate potential prototype pollution in DisplayLayoutToolbar

[RinZ27]

This PR restores the changes from #8222 to address the potential prototype pollution vulnerability.

Reference: #8222
Rationale: As noted by @akhenry, addressing this is crucial for the zero-trust security posture.

[akhenry]

@RinZ27 Thanks for resubmitting this!

[akhenry]

@RinZ27 I have had some time to look into this, thanks again for raising it to our attention. I think we will go ahead and take the change (thanks!) so please complete a CLA if you haven't already done so.

There is unguarded access of internal object properties based on a user input (a URL in this case). I do not see the potential for prototype pollution however because there is no property assignment happening. Please correct me if I'm misunderstanding the vulnerability here.

That being said, code evolves over time and there may be other attack vectors we haven't considered so I'm in favor of patching this now anyway to avoid future problems.

[RinZ27]

Thank you for your time and the detailed review, @akhenry.

I appreciate you validating the change. I agree with your assessment regarding the prototype pollution vector; while there is no direct property assignment here, guarding against unintended access to internal object properties is a prudent defense-in-depth measure to prevent future regression or obscure edge cases.

I will ensure the CLA requirements are satisfied immediately. Thanks again for moving this forward.

[RinZ27]

Signed CLA has been sent to the NASA SRA team and Kimberly Minafra. Thanks! @akhenry

[akhenry]

Fixes #8232

[akhenry]

Signed CLA has been sent to the NASA SRA team and Kimberly Minafra. Thanks! @akhenry

Thanks!