Work around fundrawtransaction consolidation

[t-bast]

We don't have any control over bitcoind's coin selection: it sometimes ends up creating transactions with a large number of inputs (and thus a high fee), which we want to avoid. We run multiple coin selection attempts in parallel and use the best result to mitigate that.

We should monitor how this behaves in practice and revert that change if it doesn't prove to be useful.

We should also push for more configuration options on the bitcoind side to get funding results that better match our transaction patterns.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (61f1e1f) 85.85% compared to head (9c49413) 85.88%.

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2807      +/-   ##
==========================================
+ Coverage   85.85%   85.88%   +0.03%     
==========================================
  Files         216      216              
  Lines       18188    18203      +15     
  Branches      780      782       +2     
==========================================
+ Hits        15615    15634      +19     
+ Misses       2573     2569       -4     

Files	Coverage Δ
...cinq/eclair/channel/fund/InteractiveTxFunder.scala	93.05% <100.00%> (+0.80%)	⬆️

... and 4 files with indirect coverage changes

[t-bast]

I'm not sure we need this anymore, and bitcoind is adding more controls to limit fees paid, so let's shelve this for now.