Fixed a runtime error caused by the Pills Container component trying to access an undefined icon.

[shadwar123]

Fixes #3138

Additional description

The Pills Container component was encountering a runtime error because it tried to access an icon that was sometimes undefined. To fix this, I applied optional chaining where the icon is being updated. If the icon is not present, we set its value to null. As a result, the getAvatar() function is called, and the props are passed with icon = null and avatar = value. In the Utilities, there's a Pill component that renders either the icon or the avatar based on their values using render() function.
@interactivellama

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[salesforce-cla]

Thanks for the contribution! Before we can merge this, we need @shadwar123 to sign the Salesforce Inc. Contributor License Agreement.

[interactivellama]

Thanks for picking this up! Please remove the package lock file changes unless you are updating dependencies.

[interactivellama]

What is the situation that this.props becomes undefined within?

[shadwar123]

Actually the undefined problem is comming beacuse of selected-listbox.jsx getIcon funtion as In some cases option only have icon or in other case only avatar, there i have applied const iconObject = option?.icon || null; and here const icon = this.props?.icon || this.props?.avatar; for the extra safety.

[interactivellama]

I see that you downgraded the package lock verison. Please remove your package.lock file.

[shadwar123]

I see that you downgraded the package lock verison. Please remove your package.lock file.

Done,
Actually to run the program i have to run this npm install --legacy-peer-deps which changes Package-lock.json file.
Now I have removed the Package-lock.json file.

[interactivellama]

@shadwar123 You shouldn't delete package-lock files in libraries you are contributing to. Please restore the old version.

[shadwar123]

@shadwar123 You shouldn't delete package-lock files in libraries you are contributing to. Please restore the old version.

Done.

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