added light_map to material spec

[jennuine]

🦟 Bug fix

Related to #639, changes will need to be ported to later versions to fully resolve.

Summary

Added missing //light_map from //material/pbr/metal and //material/pbr/specular specification.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[iche033]

note the matching DOM classes are only available in sdf10, added in #429. It may be ok - it just means that the field just won't be accessible through the PbrWorkflow class in sdf9.

[chapulina]

it just means that the field just won't be accessible through the PbrWorkflow class in sdf9.

I think this can become confusing for downstream users. We should be moving towards parity between the XML spec and the C++ classes.

[jennuine]

note the matching DOM classes are only available in sdf10, added in #429.

I looked at the wrong branch earlier, thank you for pointing that out.

I think this can become confusing for downstream users. We should be moving towards parity between the XML spec and the C++ classes.

I think it's currently confusing for downstream users now since //light_map is in the 1.7 spec but only in sdf10 and not sdf9. I think we should backport #429 to sdf9 for consistency.

I'll close this PR and open a new one with the backport.

[jennuine]

Backport PR: #648