Install bash completion script

[scpeters]

Follow-up to gazebosim/sdformat#1042. Fixes unstable nightly builds.

https://build.osrfoundation.org/job/sdformat13-debbuilder/454/

[scpeters]

test build:

• https://build.osrfoundation.org/job/sdformat13-debbuilder/456/

[chapulina]

Maybe all the CLI files should be installed in the non-dev package? See

• libignition-gazebo[2-6]-dev debs should not be required to run simulation using ign gazebo-tooling/release-tools#529

[scpeters]

Maybe all the CLI files should be installed in the non-dev package? See

• libignition-gazebo[2-6]-dev debs should not be required to run simulation using ign gazebo-tooling/release-tools#529

I'd prefer to address that issue in a separate set of PRs since this is just trying to fix the unstable nightly build

[chapulina]

I'd prefer to address that issue in a separate set of PRs since this is just trying to fix the unstable nightly build

Ok, I was trying to avoid the extra work, since fixing all the nightlies will involve lots of PRs to lots of versions and libraries. And then updating the package that it goes with will require another set of PRs to the same places.

By the way, @azeey is on this task already.