Source /custom-data/setup.bash on sysroot build

[hidmic]

Just a means to control the build environment. I do not have a strong opinion about how this is achieved (as long as there is a way). As such, I'm open to completely changing this patch if a more suitable alternative exists.

Thanks for the tool BTW !

[emersonknapp]

LGTM - I've got no concerns with this

[hidmic]

Most jobs are failing because of unrelated reasons. I have to take a closer look at the shellcheck one though.

[hidmic]

Rebased to please workflows.

[codecov]

Codecov Report

Merging #322 (acaa7c1) into master (2795a54) will not change coverage.
The diff coverage is n/a.

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@@           Coverage Diff           @@
##           master     #322   +/-   ##
=======================================
  Coverage   93.23%   93.23%           
=======================================
  Files          11       11           
  Lines         414      414           
=======================================
  Hits          386      386           
  Misses         28       28           

Flag	Coverage Δ
unittests	93.23% <ø> (ø)

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[TSC21]

Does this mean we can eventually use this to support workspace overlaying and so answer to #299?

[emersonknapp]

It seems like you could mount an underlay workspace into the custom-data-dir, then source it in custom-data/setup.bash - so theoretically yes, though I haven't tried it. Would love to hear back if that works, and if so, an addition to the README explaining this workflow would be really useful.