KRACOEUS-8272 Save/Save and Continue should not render when a proposal i...

...s in read only mode
Should use a constant here. I'd also prefer is we use PD specific constants, not Rice ones when we define them. In this case we define and use modifyProposal in the Document authorizer. Make that a constant and you should be able to use the view context defined #proposalAuthConstants instead of the full class name as well. Check out ProposalBudgetPage.xml for some examples of this.