7b8e15728d1ad058a4b7d7569fd5d5ba6806ca28 rpc: Fix rpcRunLater race in walletpassphrase (João Barbosa)
Pull request description:
Release locks before calling `rpcRunLater`.
Quick explanation: `rpcRunLater` leads to `event_free` which calls `event_del` which can wait for the event callback to finish if it's already running and that callback will try to lock wallet mutex - which is already locked in http thread.
Fixes #14995 , fixes #18482. Best reviewed with whitespace changes hidden.
Backport of Core PR18487
Fixes https://github.com/Bitcoin-ABC/bitcoin-abc/issues/375