test: Reformat python imports to aid scripted diff
https://github.com/bitcoin/bitcoin/pull/16898/commits/1111bb91f517838e5b9f778bf6b5a9c8d561e857
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test: Use connect_nodes when connecting nodes in the test_framework
https://github.com/bitcoin/bitcoin/pull/16898/commits/faaee1e39a91b3f603881655d3980c29af09852b
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scripted-diff: test: Replace connect_nodes_bi with connect_nodes
```-BEGIN VERIFY SCRIPT-
sed -i --regexp-extended -e
's/connect_nodes_bi\(self.nodes,\s*(.),\s*/connect_nodes(self.nodes[\1],
/g' $(git grep -l connect_nodes_bi)
sed -i --regexp-extended -e 's/connect_nodes_bi(,| )/connect_nodes\1/g'
$(git grep -l connect_nodes_bi)
-END VERIFY SCRIPT-```
https://github.com/bitcoin/bitcoin/pull/16898/commits/fa3b9ee8b2280af4bcbcfffff275aaf8dd125929
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test: Remove unused connect_nodes_bi
https://github.com/bitcoin/bitcoin/pull/16898/commits/fadfd844de8c53034a97dfa6f771ffe9f523fba2
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Had to adapt changes to our connect_nodes API that does not take an int for second parameter
`abc-parkedchain` was failing, seemed like one of the nodes was banning the other partway thru the test. `abc-finalize-block` also failed, seemed it depended on the old behavior of test_framework.py's `setup_network()`, changed it so that alt_node connects to node and not the other way around
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Backport of Core PR16898