APT source whitelist request for ppa:octave/stable

[BanzaiMan]

This replaces travis-ci/travis-ci#4279.

The original text by @cbm755 follows

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Required for testing Octave-based software (such as https://github.com/cbm755/octsympy, and https://github.com/catch22/octave-doctest).

Should be tagged apt-source-whitelist apt-whitelist but I don't see how to do so...

thanks

[zarquon42b]

any progress? Also, there seems to be the label missing.

[scottclowe]

:+1: +1

[erip]

:+1: Please consider finishing this!

[roversch]

👍 Yes please!