All proposals start to be voted on when they are created

[karynemayer]

Overview

Because we don't have a interface for enabling the voting of a ballot at a later date, we would like to remove the ability from the form until we add it. This way, we don't lock out non-technical users from the ballot creation flow.

Acceptance criteria

• At the step of selecting the voting time for the ballot, we always assume it will be opened at the creation time
• The checkbox is checked, but disabled so the user can't change it
• The message Proposals will be eligible for voting once they are created. should appear

Technical considerations

Tasks

• Disable the checkbox
• Add the message
• Ask @donnyquixotic about the message before opening the PR