Emailer - Fix stage 1 dissolution processor MRAS flow issue

[argush3]

As a part of the work done in #21760, it was determined that the stage 1 dissolutions email processor was not pointing at v2 of legal api endpoints. A test was done to point the emailer in dev at v2 legal api endpoints and that resulted in a successful call to the MRAS endpoint but an error in processing the MRAS http response.

After further analysis, it was determined that we should hold off on the fix in this ticket as updating the emailer to use v2 would break existing functionality in other email processors.

Work for this ticket can be done after #22431 has been completed.

TODOs

• Update stage 1 emailer processor MRAS flow as appropriate so it can properly send out an email. Believe there was an issue processing a valid MRAS http response at the time of testing. Reference comments in Emailer - stage 1 overdue ARs notification (letter attachment excluded) #21760 for more details of error.

- [ ] Add/update unit tests as appropriate