```
When a wallet is loaded which has an unconfirmed transaction in the mempool, it will end up establishing the lock order of cs_wallet -> cs_main -> cs_KeyStore. If dumpwallet is used on this wallet, then a lock order of cs_wallet -> cs_KeyStore -> cs_main will be used, which causes a lock order assertion. This PR fixes this by reordering dumpwallet and GetKeyBirthTimes (only used by dumpwallet). Specifically, in both functions, the function calls which lock cs_main are done prior to locking cs_KeyStore. This avoids the lock order issue.
Additionally, I have added a test case to wallet_dump.py. Of course testing this requires --enable-debug.
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Backport of core#22492.