Update to Julia 1.3.0

[fergu]

This just updates two lines to have the build pull down Julia 1.3.1 (Most current as of Dec 30 2019). The first is the variable JULIA_VERSION, the second is the associated checksum for the tar.gz file.

[fergu]

This should have been titled Julia 1.3.1 as that is what this is actually doing, not 1.3.0. PR #965 updates to 1.3.0.

[Bidek56]

@parente Do you need help with these PRs? I have noticed that they have been accumulating :)

[parente]

Thanks @kjfergu and @Bidek56. I'm taking a pass through the PRs now and merging.

[Nosferican]

Could we get this tagged at Docker Hub?

[parente]

@Nosferican Images with Julia 1.3.1 are now being tagged on Docker Hub after the build process fix mentioned in #992. The tags follow the git sha standard we use for all the images here (https://github.com/jupyter/docker-stacks/wiki).

If you're interested in seeing additional Julia interpreter versions as tags like we have for Python versions and Jupyter notebook, lab, and hub versions, I'd welcome a PR adding them. A script like this one https://github.com/jupyter/docker-stacks/blob/master/base-notebook/hooks/apply_tags needs to be implemented and placed in https://github.com/jupyter/docker-stacks/blob/master/datascience-notebook/hooks/apply_tags.