gpos_kerning_info doesn't notice contextual kerning

[bobh0303]

SIL's Harmattan font does kerning exclusively by contextual GPOS kerning rules that invoke GPOS single adjustments — there are no pair kerning rules.

Observed behaviour

gpos_kerning_info test generates a warning:

WARN GPOS table lacks kerning information. [code: lacks-kern-info]

Expected behaviour

Should PASS

Resources and steps needed to reproduce

• Download zip file containing SIL's Harmattan font package from https://software.sil.org/harmattan/download/
• Unpack zip file
• Navigate to the ttf files and execute the command:

fontbakery check-opentype -c gpos_kerning_info Harmattan-Regular.ttf -v

Fontbakery version: 0.12.10.dev0+g2bb3b911.d20240803 (running from source)
Platform: Ubuntu 24.04 LTS (within Docker on Windows 10 host).