Prompt user for JIRA ticket and supply it to upload.py

It's cumbersome to have to enter the ticket number several times in

cr --rev=$(git merge-base master HEAD) --jira=<YOUR_JIRA_TICKET> --title="<YOUR_JIRA_TICKET> <PATCH_DESCRIPTION>" --description="https://jira.mongodb.org/browse/<YOUR_JIRA_TICKET>"

It would be better if we prompted the user for it or took it as an option. We could also try parsing it from the branch name.