Fix link to yj in bionic build Dockerfile. (#130)

[robdimsdale]

Closes #128 ; based off #130

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[fgrehm]

Thanks for the quick turnaround here folks! Really appreciated ❤️

@sophiewigmore @robdimsdale I'm kinda new to paketo projects' workflows but is this something that requires manual intervention for a release or will it be automagically created like at some point this week? We rebuild our builders on a weekly basis (monday mornings) so we're wondering if we should just lock our imgs to an upstream build stack tag that we know for sure will have an usable yj (to avoid breaking our devs builds) or if we can just chill and let it automatically get latest next monday.

Also, if there's anything I can do to help test things out to help with that release please LMK too! 🍻

[sophiewigmore]

@fgrehm the change will take effect when the releases come out, but our automation doesn't allow for a release to come out unless there's a change to the packages in the image. Because of this, we're kind of at the mercy of a package update (which happen every few days usually). I'd say we can rely on a release coming out in the next week, looking at the release cadence in the past. Our automation checks for updates everyday, and will also get updated when a USN comes out for a CVE.

The next release should contain the functional yj, so you should be good to just consume the next release!

[sophiewigmore]

@fgrehm the good news is that I just triggered a release of the full stack and there was a package update so paketobuildpacks/build:1.3.34-full-cnb is available and looks like yj is functional!! I'll do the same for base and tiny stacks as well.

[fgrehm]

You're awesome! Thank you very much 🙇