refactor, misc: remove CBitcoin(Address|Secret) #3129

Job	Run time
Lint	49s
ARM [GOAL install] [buster]	8m 24s
Win32	10m 10s
macOS 12 native [GOAL install] [GUI] [no depends]	12m 24s
Win64	13m 40s
i386 Linux [GOAL install] [focal]	8m 16s
x86_64 Linux [GOAL install] [GUI] [focal] [no depends]	16m 43s
x86_64 Linux [GOAL install] [GUI] [bionic] [no depends]	15m 58s
x86_64 Linux [ASan] [LSan] [UBSan] [integer] [jammy] [no depends]	15m 37s
macOS 10.14 [GOAL deploy] [GUI] [no tests] [focal]	10m 11s
	1h 52m 12s

Provide feedback