[ANN] orcus 0.15.4 on master

[Kohei Yoshida]

Hi there,

FYI, I've updated the orcus package to 0.15.4 on master.  This is just a 
bugfix release to only address build and packaging issues.

Please refer to

https://gitlab.com/orcus/orcus/-/releases/0.15.4

for the specific changes of this release.

Thanks,

Kohei