docs: Build the installation guide instead of "all"
docs: Build the installation guide instead of "all"

It seems that all the work is going into the installation guide instead
of the "-all" docs.

With this commit we build the installation guide documentation.

DaanHoogland/cloudstack,DaanHoogland/cloudstack,GabrielBrascher/cloudstack,DaanHoogland/cloudstack,wido/cloudstack,GabrielBrascher/cloudstack,resmo/cloudstack,GabrielBrascher/cloudstack,resmo/cloudstack,jcshen007/cloudstack,jcshen007/cloudstack,wido/cloudstack,resmo/cloudstack,wido/cloudstack,mufaddalq/cloudstack-datera-driver,resmo/cloudstack,mufaddalq/cloudstack-datera-driver,DaanHoogland/cloudstack,mufaddalq/cloudstack-datera-driver,resmo/cloudstack,GabrielBrascher/cloudstack,mufaddalq/cloudstack-datera-driver,DaanHoogland/cloudstack,jcshen007/cloudstack,mufaddalq/cloudstack-datera-driver,wido/cloudstack,wido/cloudstack,DaanHoogland/cloudstack,GabrielBrascher/cloudstack,jcshen007/cloudstack,GabrielBrascher/cloudstack,jcshen007/cloudstack,jcshen007/cloudstack,DaanHoogland/cloudstack,wido/cloudstack,mufaddalq/cloudstack-datera-driver,GabrielBrascher/cloudstack,resmo/cloudstack,resmo/cloudstack,jcshen007/cloudstack,wido/cloudstack