Unintentional stage-up of PR branch on a non-PR branch

[vivekbisen]

When called op stage-up on a branch that doesn't have a PR, octopolo is expected to prompt users for PR number. It unintentionally stages up PR branch that matches the current branch name.

In the example below, PR 11236 is associated with branch name masteronlyordercont

[vivekbisen]

Possible solutions would be asking github for an exact match of the branch name or doing it ourselves around this line instead of accepting the first result.