Set environment configuration into docker context generator

[dzmitryh]

This small pr addresses the issue mentioned in the issue -> #890

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[TadCordle]

Hi @dzmitryh, thanks for the contribution, however I actually just fixed this already and am working on releasing 0.9.13 with the changes. I probably should have tagged the original issue in my PRs so it showed up in the thread; sorry!

[dzmitryh]

@TadCordle no worries, thanks for pushing it forward. Looking forward to see 0.9.13 with that fix.