fix(universal-xml-plugin): add checks to disable the plguin in webview

[sudharsan-selvaraj]

Proposed changes

Currently finding elements in webview is not working when the plugin is enabled. Added a check to make sure the plugin transforms the XML source only when the application context is set to NATIVE_APP.

Fixes #20060

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[jlipps]

thanks @sudharsan-selvaraj !