test: add coverage for 'add_inputs' dynamic default value
test: add coverage for 'add_inputs' dynamic default value

Covered cases for send() and walletcreatefundedpsbt() RPC commands:

1. Default add_inputs value with no preset inputs (add_inputs=true):
       Expect: automatically add coins from the wallet to the tx.

2. Default add_inputs value with preset inputs (add_inputs=false):
       Expect: disallow automatic coin selection.

3. Explicit add_inputs=true and preset inputs (with preset inputs not-covering the target amount).
       Expect: include inputs from the wallet.

4. Explicit add_inputs=true and preset inputs (with preset inputs covering the target amount).
       Expect: only preset inputs are used.

5. Explicit add_inputs=true, no preset inputs (same as (1) but with an explicit set):
       Expect: include inputs from the wallet.

ajtowns/bitcoin,sstone/bitcoin,ajtowns/bitcoin,mruddy/bitcoin,bitcoin/bitcoin,bitcoin/bitcoin,AkioNak/bitcoin,tecnovert/particl-core,particl/particl-core,fanquake/bitcoin,lateminer/bitcoin,jambolo/bitcoin,namecoin/namecoin-core,lateminer/bitcoin,AkioNak/bitcoin,sstone/bitcoin,lateminer/bitcoin,namecoin/namecore,namecoin/namecore,AkioNak/bitcoin,fanquake/bitcoin,lateminer/bitcoin,fanquake/bitcoin,particl/particl-core,mruddy/bitcoin,mruddy/bitcoin,mruddy/bitcoin,sstone/bitcoin,fujicoin/fujicoin,namecoin/namecore,bitcoin/bitcoin,namecoin/namecore,ajtowns/bitcoin,particl/particl-core,tecnovert/particl-core,AkioNak/bitcoin,namecoin/namecoin-core,kallewoof/bitcoin,ajtowns/bitcoin,fanquake/bitcoin,kallewoof/bitcoin,mruddy/bitcoin,bitcoinsSG/bitcoin,bitcoin/bitcoin,bitcoin/bitcoin,particl/particl-core,fujicoin/fujicoin,jambolo/bitcoin,fanquake/bitcoin,sstone/bitcoin,fujicoin/fujicoin,bitcoinsSG/bitcoin,ajtowns/bitcoin,bitcoinsSG/bitcoin,bitcoinsSG/bitcoin,jambolo/bitcoin,bitcoin/bitcoin,lateminer/bitcoin,bitcoinsSG/bitcoin,sipsorcery/bitcoin,tecnovert/particl-core,fujicoin/fujicoin,kallewoof/bitcoin,jambolo/bitcoin,particl/particl-core,sipsorcery/bitcoin,namecoin/namecoin-core,sstone/bitcoin,sstone/bitcoin,AkioNak/bitcoin,namecoin/namecoin-core,sipsorcery/bitcoin,AkioNak/bitcoin,lateminer/bitcoin,fanquake/bitcoin,bitcoinsSG/bitcoin,namecoin/namecore,jambolo/bitcoin,fujicoin/fujicoin,mruddy/bitcoin,tecnovert/particl-core,jambolo/bitcoin,tecnovert/particl-core,kallewoof/bitcoin,namecoin/namecoin-core,sipsorcery/bitcoin,namecoin/namecoin-core,ajtowns/bitcoin,tecnovert/particl-core,fujicoin/fujicoin,namecoin/namecore,sipsorcery/bitcoin,kallewoof/bitcoin,particl/particl-core,kallewoof/bitcoin,sipsorcery/bitcoin