`self.nodes[0]` creates an address which is watch-only-shared with `self.nodes[3]`. If `nodes[0]` spends the associated UTXO during any of its sends later, the watchonly test will fail, as `nodes[3]` now has insufficient funds.

I ran into this in #12257 and this commit is in that PR as well, but I figured I'd split it out (and remove from there once/if merged).

test_runner.py