[S] Change in coreboot[main]: docker/coreboot-jenkins-node/Dockerfile: apt install sphinx

[Martin L Roth (Code Review)]

Attention is currently required from: Elyes Haouas.

Martin L Roth has posted comments on this change by Elyes Haouas. ( https://review.coreboot.org/c/coreboot/+/76739?usp=email )

Change subject: docker/coreboot-jenkins-node/Dockerfile: apt install sphinx
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Patch Set 1: Code-Review-1

(1 comment)

Patchset:

PS1: 
We want to have a separate virtual environment so that we can specify versions rather than relying on the versions that the OS wants to install.