Deleting environments - provide PR title linking to issue on GitHub

Most of the time we use GH for environments. 

It would be nice to use GitHub API to get the PR title so i can see what the environment is being used for on Github when working out whether to delete the environment.

Select environments to delete:

`- pr-1349 (<Pr Title> - <link to PR>)` T


This information could be gained via the `gh` tool if it is installed on the system