chore: use src layout

[mayeut]

Allows better test isolation & thus, test the sdist / wheel without the legacy layout interfering.

depends on #331

[codecov]

Codecov Report

Merging #332 (b4de8f4) into master (16b2e80) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #332   +/-   ##
=======================================
  Coverage   89.54%   89.54%           
=======================================
  Files          23       23           
  Lines        1244     1244           
  Branches      270      270           
=======================================
  Hits         1114     1114           
  Misses         79       79           
  Partials       51       51           

Impacted Files	Coverage Δ
src/auditwheel/__main__.py	0.00% <ø> (ø)
src/auditwheel/condatools.py	91.66% <ø> (ø)
src/auditwheel/elfutils.py	94.05% <ø> (ø)
src/auditwheel/error.py	100.00% <ø> (ø)
src/auditwheel/genericpkgctx.py	50.00% <ø> (ø)
src/auditwheel/hashfile.py	100.00% <ø> (ø)
src/auditwheel/lddtree.py	87.17% <ø> (ø)
src/auditwheel/libc.py	87.50% <ø> (ø)
src/auditwheel/main.py	100.00% <ø> (ø)
src/auditwheel/main_addtag.py	86.84% <ø> (ø)
... and 13 more

---

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[lkollar]

LGTM but I can't figure out why the coverage has dropped so much. Any ideas @mayeut?

[mayeut]

I can't figure out why the coverage has dropped so much. Any ideas @mayeut?

Taking a closer look at this, it seems all manylinux tests are skipped. I need to take a closer look to see what's wrong here...

[mayeut]

I can't figure out why the coverage has dropped so much. Any ideas @mayeut?

Taking a closer look at this, it seems all manylinux tests are skipped. I need to take a closer look to see what's wrong here...

This now fixed and coverage is back to no diff which is expected.