Fix Apache license version (backport to edifice)

[scpeters]

Backport #325 to edifice. Use rebase and merge.

[chapulina]

It could be backported to Citadel and then it joins the forward-port train to Edifice

[codecov]

Codecov Report

Merging #327 (a18e5d6) into ign-physics4 (9e03297) will not change coverage.
The diff coverage is n/a.

@@              Coverage Diff              @@
##           ign-physics4     #327   +/-   ##
=============================================
  Coverage         75.84%   75.84%           
=============================================
  Files               127      127           
  Lines              5734     5734           
=============================================
  Hits               4349     4349           
  Misses             1385     1385           

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[scpeters]

It could be backported to Citadel and then it joins the forward-port train to Edifice

I made the backport to Citadel first in #326, but one of the modified files did not exist in Citadel, so I need to backport here as well

[scpeters]

It could be backported to Citadel and then it joins the forward-port train to Edifice

I made the backport to Citadel first in #326, but one of the modified files did not exist in Citadel, so I need to backport here as well

I suppose I could have made a separate commit that only touched dartsim/src/WorldFeatures_TEST.cc, but it was easier to just cherry pick the whole commit

[scpeters]

It could be backported to Citadel and then it joins the forward-port train to Edifice

I made the backport to Citadel first in #326, but one of the modified files did not exist in Citadel, so I need to backport here as well

dartsim/src/WorldFeatures_TEST.cc was added to edifice in https://github.com/ignitionrobotics/ign-physics/pull/225/files#diff-5f37fd0659e70bb363f58b8b28d459b9007ee5a8b9d5a382c3875ff320a27550R4