gui: Remove WalletView and BitcoinGUI circular dependency

Summary:

Essentially moves the code in WalletView::setBitcoinGUI to the only caller.

Remove the circular dependency "qt/bitcoingui -> qt/walletview -> qt/bitcoingui"

This is a backport of Core PR17937 [2/2]
https://github.com/bitcoin/bitcoin/pull/17937/commits/cb8a86d9f952401eaad68b2e3818ce50f7befd91

Depends on D8698

Test Plan:
ninja && src/qt/bitcoin-qt
Test some of the connections

Run test/lint/lint-circular-dependencies.sh

Reviewers: #bitcoin_abc, majcosta

Reviewed By: #bitcoin_abc, majcosta

Differential Revision: https://reviews.bitcoinabc.org/D8699