Channels: Fix community tab

[Fijxu]

May close #5182

API works well too.

If I need to change anything, just tell me

[Fijxu]

Here I didn't replace "community" by "posts". I left it as a fallback.

[ChunkyProgrammer]

Suggestion: Since the url didn't change and just the text, maybe this can be handled similarly to how channel live tab is handled? (1 ternary statement that changes live to streams, in this case change post to community).

invidious/src/invidious/channels/about.cr

Lines 105 to 112 in 164d764

	tab_names = tabs_json.as_a.compact_map do |entry|
	name = entry.dig?("tabRenderer", "title").try &.as_s.downcase
	# This is a small fix to not add extra code on the HTML side
	# I.e, the URL for the "live" tab is .../streams, so use "streams"
	# everywhere for the sake of simplicity
	(name == "live") ? "streams" : name
	end