Update templates.json for Event Hubs templates to use 5.0.0 extension version

[mattchenderson]

The package references for all Event Hubs templates should be updated to use the new extension version.

[fabiocav]

@AnatoliB would you be able to have this assigned? @soninaren would be able to provide assistance here if needed.

[shreyabatra4]

Hi @JoshLove-msft, can you please help to take a look at this issue for defaulting new function applications to Track 2 extensions? The requested action is to update the templates such that they refer to the extension bundle version "[3.*, 4.0.0)" in the file 'host.json'. and to update the nuget references in the Track 2 templates for .NET to reference the Track 2 extensions.