Scenes with "Auto generate" lightmaps can have invalid m_LightingDataAsset reference

[kipash]

Repro steps

• Create a new scene
• Bake lightmaps manually
• Switch to auto bake
• Delete the lightmaps from project that are no longer used
• Observe the issue

While Auto generate is true, reporting m_lightingDataAsset having a missing reference is missleading.

Invalid reference for m_LightingDataAsset should be ignored if m_GIWorkflowMode: 0 (autogenerate is true)

Unity version: 2020.3.43f1