Update Playbook Project webview to use @vscode-elements package

[shatakshiiii]

This PR updates Ansible playbook project webview to use @vscode-elements/elements package
instead of now deprecated @vscode/webview-ui-toolkit.

Updated related code and styles and tests.

For https://github.com/vscode-elements package info refer: https://vscode-elements.github.io/guides/getting-started/

Related: AAP-37623

[shatakshiiii]

Codecov is failing unexpectedly. These changes are updated in the UI test: "Test Ansible playbook and collection project scaffolding". This is a false positive.

[abhikdps]

I tested this locally and it seems that clicking on the Clear All Button does not clear the text fields, i.e the Namespace and Collection fields are not getting cleared. Other than this, everything else looks good!