CompatHelper: bump compat for GLMakie to 0.6, (keep existing compat)
This pull request changes the compat entry for the GLMakie
package from 0.5
to 0.5, 0.6
.
This keeps the compat entries for earlier versions.
Note: I have not tested your package with this new compat entry. It is your responsibility to make sure that your package tests pass before you merge this pull request.