Install ign-plugin executable

[scpeters]

Fix unstable build:

• https://build.osrfoundation.org/view/ign-garden/job/ign-plugin2-debbuilder/327/

testing with this branch

• https://build.osrfoundation.org/view/ign-garden/job/ign-plugin2-debbuilder/328/

[j-rivero]

Changes will require gazebosim/gz-plugin#80.

Fixed:

• The cli app should be placed into libexec and should not in a dev package if possible but in its own package d4bebc3
• Removed Debian Sid since it has its own package ea55ede
• Seems like doc-base was complaining about bad paths, do not use wildcards there e483eed
• lintian exception was broken 6c68ec5

[chapulina]

@j-rivero , adding a new package for the CLI looks like a different approach from the one suggested for Transport in

• Use libexec for new cli paths gz-transport11-release#4

Should we use the same pattern for all libraries?

[j-rivero]

Testing it here

[scpeters]

Testing it here

looks good to me

I would approve but I'm the author of this PR

[scpeters]

I'll just go ahead and merge