use fixed-width font for script display/edit

[ombre42]

fixed-width font (mono space) is used for the *nix and Windows scripting built-in plugins for Jenkins as well as being more popular for coding overall

[buildhive]

Jenkins » python-plugin #2 SUCCESS
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[kohsuke]

Thank you for a pull request! Please check this document for how the Jenkins project handles pull requests

[jhasse]

Bumping this rather old PR ;)

Can this be merged? It's a trivial change, but it would improve readability a lot.

[axel-h]

Can we get this on in, please?

[jhasse]

Actually I would now rather like to see this PR merged: #2

[axel-h]

yes, that one look even better.

[jhasse]

Fixed by #2