Lightmap Coordinate Index is not automatically set to 1 on import any longer with lightmap UV

When importing a static mesh with a second UV channel setup for the lightmap the second UV is no longer being automatically assigned as the lightmap coordinate index. In 4.12 the second UV detected in the FBX would automatically be assigned LM Coordinate Index 1.

Working: 4.12.5 CL-3039270
Broken: 4.13 CL-3106830
Broken: 4.14 Dev-Main CL-3109838

1. Import any mesh with a base UV for textures and a second UV for the lightmap (Use the attached asset if needed)
2. Uncheck Auto Generate Lightmap UVs in the Import options window
3. Open the static mesh once imported
4. Look at the Lightmap Coordinate Index assigned

Regression: Yes

Results: Lightmap coordinate index is no longer assigned on import to UV channel 1.

Expected: When importing a lightmap UV it should be assigned to channel 1 by default.