[ie/NBCStations]allow for new nbc_data syntax

[refack]

Description of your pull request and other information

NBC affiliate sites seem to be using new Object.assign(nbc, {... syntax for assigning to the nbc global var

Fixes #

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[bashonly]

I'd prefer to avoid the .+? and do this

Suggested change

	r'<script>(?:\s*var\s+nbc\s*=|.+?Object\.assign\(nbc,\s*)', webpage, 'NBC JSON data', video_id)
	r'(?:<script>?:\s*var\s+nbc\s*=|Object\.assign\(nbc,)', webpage, 'NBC JSON data', video_id)

[refack]

For posterity, the new assign syntax is:

<script>if ("undefined" === typeof nbc) {var nbc = {};}; Object.assign(nbc, {"brand":"nbc",...