[Trivial] filter out empty solutions when quoting (#2072)

# Description
We are seeing a lot of WARN logs for orders that can't be quoted a la:

> driver::infra::observe: failed to quote order order=Order { tokens:
Tokens { sell:
TokenAddress(ContractAddress(0xf939e0a03fb07f59a73314e73794be0e57ac1b4e)),
buy:
TokenAddress(ContractAddress(0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2))
}, amount: TargetAmount(100000000000000000), side: Buy, deadline:
Deadline { driver: 2023-11-23T07:58:46.894119698Z, solvers:
2023-11-23T07:58:45.995982488Z } }
err=QuotingFailed(ClearingSellMissing)

This is because some solvers instead of returning no solution return the
"trivial" solution if they cannot solve the auciton:

> solvers::api::routes::solve: auction_id=Quote solutions=[Solution {
id: Id(0), prices: ClearingPrices({}), trades: [], interactions: [],
score: RiskAdjusted(SuccessProbability(1.0)) }]

Since this warning looks a bit cryptic and we already do have an error
for NoSolutions, this PR makes it that we instead show

> /quote{solver=baseline}: driver::infra::observe: failed to quote order
order=Order { tokens: Tokens { sell:
TokenAddress(ContractAddress(0x15f74458ae0bfdaa1a96ca1aa779d715cc1eefe4)),
buy:
TokenAddress(ContractAddress(0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2))
}, amount: TargetAmount(100000000000000000), side: Buy, deadline:
Deadline { driver: 2023-11-23T08:04:36.803626137Z, solvers:
2023-11-23T08:04:35.904046019Z } } err=QuotingFailed(NoSolutions)

# Changes
Filter out empty solutions before passing them to create an invalid
quote.

## How to test
Run locally, get a quote which cannot be filled, observe logs

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## Related Issues

Fixes #
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crates/driver/src/domain/quote.rs

@@ -98,7 +98,7 @@ impl Order {
             // first solution
             solutions
                 .into_iter()
-                .next()
+                .find(|solution| !solution.is_empty())
                 .ok_or(QuotingFailed::NoSolutions)?,
         )
     }