[backport#10953] [Refactor] Combine scriptPubKey and amount as CTxOut in CScriptCheck

Summary:
3a131b724 Rename out to m_tx_out in CScriptCheck (Johnson Lau)
e91211878 [Refactor] Combine scriptPubKey and amount as CTxOut in CScriptCheck (Johnson Lau)

Pull request description:

This simplifies CScriptCheck by combining scriptPubKey and amount

Backport of Core PR10953

Test Plan:

ninja check && ninja check-functional

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D6932