Book test issues

[fingolfin]

While trying to understand why the book tests failed on a PR of mine (I think it was a fluke in the end?), I had a look at this log, and noticed some things I find concerning:

First off, this looks as if some files are included multiple times?

WARNING: Method definition base_coefficient_rings(Array{var"#s631", 1} where var"#s631"<:(AbstractAlgebra.MPolyRingElem{T} where T)) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:4 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition collect_terms(Array{var"#s631", 1} where var"#s631"<:(AbstractAlgebra.MPolyRingElem{T} where T)) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:10 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition factorise_terms(Base.Dict{K, V} where V where K) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:36 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition factorize_collected_terms(Array{var"#s631", 1} where var"#s631"<:(AbstractAlgebra.MPolyRingElem{T} where T)) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:44 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition tropical_base(Array{var"#s631", 1} where var"#s631"<:(Base.Dict{K, V} where V where K)) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:50 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition modified_support(Array{var"#s631", 1} where var"#s631"<:(AbstractAlgebra.MPolyRingElem{T} where T)) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:63 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition nonlinear_resonator_system(Int64, Int64) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:101 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition kwcall(NamedTuple{names, T} where T<:Tuple where names, typeof(__228.nonlinear_resonator_system), Int64, Int64) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:101 overwritten on the same line (check for duplicate calls to `include`).
WARNING: Method definition generic_root_count(Array{var"#s631", 1} where var"#s631"<:(AbstractAlgebra.MPolyRingElem{T} where T)) in module __228 at /tmp/jl_eORcuY/generic_root_count/src/main.jl:124 overwritten on the same line (check for duplicate calls to `include`).
  closing mockrepl: Main.__228
specialized/bies-turner-string-theory-applications
  created mockrepl: Main.__230
    SU5.jlcon

....

Then this one (this might be relevant for @thofma and @fieker as it seems to be in the number theory chapter?). Notice the "core dumped" in the middle

┌ Warning: possibly wrong file type: cornerstones/number-theory/intro_plot_lattice.jlcon
└ @ Main ~/work/Oscar.jl/Oscar.jl/test/book/test.jl:241
WARNING: using deprecated binding Colors.RGB1 in PlotUtils.
, use XRGB instead.
WARNING: using deprecated binding PlotUtils.RGB1 in Plots.
, use ColorTypes.XRGB{T} where T<:Union{AbstractFloat, FixedPointNumbers.FixedPoint{T, f} where f where T<:Integer} instead.
WARNING: using deprecated binding Colors.RGB4 in PlotUtils.
, use RGBX instead.
WARNING: using deprecated binding PlotUtils.RGB4 in Plots.
, use ColorTypes.RGBX{T} where T<:Union{AbstractFloat, FixedPointNumbers.FixedPoint{T, f} where f where T<:Integer} instead.
┌ Warning: backend `GR` is not installed.
└ @ Plots ~/.julia/packages/Plots/ju9dp/src/backends.jl:43

GC: pause 88.96ms. collected 324.103730MB. incr 
qt.qpa.xcb: could not connect to display 
qt.qpa.plugin: From 6.5.0, xcb-cursor0 or libxcb-cursor0 is needed to load the Qt xcb platform plugin.
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: xcb, vnc, minimal, eglfs, minimalegl, offscreen, vkkhrdisplay, linuxfb.

Aborted (core dumped)
connect: Connection refused
GKS: can't connect to GKS socket application

GKS: Open failed in routine OPEN_WS
GKS: GKS not in proper state. GKS must be either in the state WSOP or WSAC in routine ACTIVATE_WS
GKS: GKS not in proper state. GKS must be either in the state WSAC or SGOP in routine FILLAREA

GC: pause 70.75ms. collected 342.784054MB. incr 
GKS: GKS not in proper state. GKS must be either in the state WSAC or SGOP in routine FILLAREA
...
[ goes on for pages and pages ]
...

Should this happen? Is this maybe due an example that only works interactively? Should we then either disable it here, or adjust it so it works non-interactively? Or what else is going on?

BTW, the actual error that failed the log then seems to be a network issues, so hopefully intermittent, and can hopefully be ignored:

+ ERROR: BSONError: domain=15, code=13053, message=No suitable servers found (`serverSelectionTryOnce` set): [socket timeout calling hello on 'db.polymake.org:27017']