Make blacklist an optional setting in the Titlegiver plugin

[reggna]

The default setting generated for Titlegiver is simply:

"titlegiver": {}

This however fails in Titlegiver.process when checking

if parts.netloc in self.settings["blacklist"]

So, let's just make the setting optional.

[coveralls]

Pull Request Test Coverage Report for Build 14287016644

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 2 (0.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+4.2%) to 62.468%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
plugins/titlegiver/titlegiver.py	0	2	0.0%

Totals
Change from base Build 14278788294:	4.2%
Covered Lines:	1205
Relevant Lines:	1929

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💛 - Coveralls