fix: remove w3s.link default block-broker

[SgtPooki]

Note that w3s will only serve blocks that are uploaded to it.

For those that do use w3s for uploading files, they just need to pass the defaults + the gateways they want

// heliaInit config:
blockBrokers: [ 
	trustlessGateways({ 
		gateways: [
			...DEFAULT_TRUSTLESS_GATEWAYS, 
			'https://w3s.link'
		]
	})
]