Move Telecom shell commands to TelecomShellCommand

1) Move existing telecom shell commands into TelecomShellCommand
2) Make this new file available to the old Telecom commands binary

By moving shell commands to TelecomServiceImpl, we are seeing a
~10X improvement in speed when using shell commands for CTS.

Bug: 327310548
Test: atest CtsTelecomTestCases, manual shell command testing
Change-Id: Ic1d9de208cf65d058784437bf244d5279b676b9c