Ghcide: hie-bios program called without file path

[hyperfekt]

I implemented a program to provide flags to hie-bios and was dismayed to find that ghcide calls it with an empty file path. This clearly violates the hie-bios API, and the resulting requirement that bios programs provide flags without any path given, counter to the documentation of hie-bios, is not documented.

[mpickering]

This is fixed in #522 and on my fork (https://github.com/mpickering/ghcide)

[fendor]

This can be closed now