Print invalid keys when configuration parsing fails

[SimplyDanny]

Mitigates #5347.

[SwiftLintBot]

	16 Messages
📖	Linting Aerial with this PR took 1.26s vs 1.2s on main (5% slower)
📖	Linting Alamofire with this PR took 1.57s vs 1.57s on main (0% slower)
📖	Linting Brave with this PR took 9.0s vs 9.0s on main (0% slower)
📖	Linting DuckDuckGo with this PR took 4.6s vs 4.58s on main (0% slower)
📖	Linting Firefox with this PR took 10.47s vs 10.47s on main (0% slower)
📖	Linting Kickstarter with this PR took 11.05s vs 11.04s on main (0% slower)
📖	Linting Moya with this PR took 0.66s vs 0.63s on main (4% slower)
📖	Linting NetNewsWire with this PR took 3.29s vs 3.28s on main (0% slower)
📖	Linting Nimble with this PR took 0.82s vs 0.82s on main (0% slower)
📖	Linting PocketCasts with this PR took 8.93s vs 8.9s on main (0% slower)
📖	Linting Quick with this PR took 0.4s vs 0.39s on main (2% slower)
📖	Linting Realm with this PR took 11.42s vs 11.48s on main (0% faster)
📖	Linting Sourcery with this PR took 2.83s vs 2.82s on main (0% slower)
📖	Linting VLC with this PR took 1.57s vs 1.57s on main (0% slower)
📖	Linting Wire with this PR took 19.74s vs 19.72s on main (0% slower)
📖	Linting WordPress with this PR took 13.49s vs 13.48s on main (0% slower)

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