wallet: bugfix: lock wallet context before adding/removing wallet set… #321

Job	Run time
Win64 native, VS 2022	55m 6s
macOS 13 native, x86_64, no depends, sqlite only, gui	43m 3s
test each commit	0s
ASan + LSan + UBSan + integer, no depends, USDT	50m 16s
	2h 28m 25s

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