Function to edit an existing snippet. It checks if the snippet has a property for syntax resolution,
and if not, it sets the default value to false. After that, it creates and shows a webview
for editing the snippet.
Parameters
context: ExtensionContext
The extension context, used for managing the lifecycle of the webview.
Function to edit an existing snippet. It checks if the snippet has a property for syntax resolution, and if not, it sets the default value to
false. After that, it creates and shows a webview for editing the snippet.