symbol-bootstrap link command does not make transactions when voting is disabled.

[kmn]

Describe the bug
When turning a non-voting node into a voting node, the node operator must execute symbol-bootstrap link command.
symbol-bootstrap link does not make transaction when the node is not a voting node, so to execute this command, the node must be restarted and run as a voting node even though it is not.
This might cause the node sync failure, and acctually I got this error.

May I ask you to disable the restriction?

symbol-bootstrap updateVotingKeys might also have the same problem.

To Reproduce
To reproduce the behavior:

1. Run non-voting node.
2. Execute symbol-bootstrap link on the non-voting node.
3. Nothing happens. Everything is treated as nomal.

Expected behavior

1. Run non-voting node.
2. Execute symbol-bootstrap link on the non-voting node.
3. The link transaction is issued

Logs
If applicable, add the full or partial logs to help explain your problem.

Additional context
This action is neccesary for changing non-voting node into voting node.