rpcserver: return early on rejected quote

[GeorgeTsagk]

Description

When an RFQ negotiation fails we return the rfq.InvalidQuoteRespEvent event to the RPC subscriber. Previously this message was ignored, causing the RPC endpoint to only return when the timeout occured. Now we immediatelly return when an RFQ negotiation failure occurs

[coveralls]

Pull Request Test Coverage Report for Build 16077853549

Details

• 0 of 22 (0.0%) changed or added relevant lines in 1 file are covered.
• 12 unchanged lines in 4 files lost coverage.
• Overall coverage increased (+0.04%) to 39.282%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
rpcserver.go	0	22	0.0%

Files with Coverage Reduction	New Missed Lines	%
asset/group_key.go	2	62.64%
commitment/tap.go	2	72.05%
tappsbt/create.go	2	26.74%
tapchannel/aux_invoice_manager.go	6	80.51%

Totals
Change from base Build 16059643780:	0.04%
Covered Lines:	30684
Relevant Lines:	78112

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💛 - Coveralls