test: fix reactor state reset after twisted.trial tests #2257

Job	Run time
python 3.9, bitcoind 28.3 on macos-13	9m 18s
python 3.9, bitcoind 29.2 on macos-13	9m 20s
python 3.13, bitcoind 28.3 on macos-13	9m 18s
python 3.9, bitcoind 28.3 on ubuntu-latest	9m 15s
python 3.13, bitcoind 29.2 on macos-13	9m 19s
python 3.13, bitcoind 29.2 on ubuntu-latest	9m 11s
python 3.13, bitcoind 28.3 on ubuntu-latest	9m 2s
python 3.9, bitcoind 29.2 on ubuntu-latest	9m 18s
	1h 14m 1s

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