Bug in documentation example

[ba2tro]

Example code in /docs/src/visualizations.md at line: https://github.com/QuantumSavory/QuantumSavory.jl/blob/master/docs/src/visualizations.md#:~:text=QuantumSavory.showmetadata(fig%2Cax%2Cplt%2C2%2C3)
causes the documentation build to fail with the stacktrace:

┌ Error: failed to run `@example` block in src/visualizations.md:68-73
│ ```@example vis
│ tag!(net[2,3], :specialplace, 1, 2)
│ tag!(net[2,3], :otherdata, 3, 4)
│ QuantumSavory.showmetadata(fig,ax,plt,2,3)
│ fig
│ ```
│   exception =
│    MethodError: no method matching vec(::Tuple{Nothing, Int64})
│    
│    Closest candidates are:
│      vec(::StrideArraysCore.PtrArray{T, 1}) where T
│       @ StrideArraysCore ~/.julia/packages/StrideArraysCore/Yyyvt/src/reshape.jl:1
│      vec(::StrideArraysCore.AbstractPtrArray{T, N, R, S, Tuple{Vararg{Nothing, N}}, O, T} where O) where {T, N, R, S}
│       @ StrideArraysCore ~/.julia/packages/StrideArraysCore/Yyyvt/src/reshape.jl:2
│      vec(::LazyArrays.ApplyArray{T, 2, typeof(hcat)} where T)
│       @ LazyArrays ~/.julia/packages/LazyArrays/jaUBE/src/lazyconcat.jl:408
│      ...
│    
│    Stacktrace:
│      [1] pick_sorted(scene::Makie.Scene, screen::CairoMakie.Screen{CairoMakie.IMAGE}, xy::GeometryBasics.Point{2, Float32}, range::Int64)
│        @ Makie ~/.julia/packages/Makie/rEu75/src/interaction/interactive_api.jl:138
│      [2] pick_sorted(scene::Makie.Scene, xy::GeometryBasics.Point{2, Float32}, range::Int64)
│        @ Makie ~/.julia/packages/Makie/rEu75/src/interaction/interactive_api.jl:124
│      [3] (::Makie.var"#1320#1321"{Makie.DataInspector, Makie.Scene})()
│        @ Makie ~/.julia/packages/Makie/rEu75/src/interaction/inspector.jl:306
│      [4] lock(f::Makie.var"#1320#1321"{Makie.DataInspector, Makie.Scene}, l::ReentrantLock)
│        @ Base ./lock.jl:229
│      [5] on_hover
│        @ ~/.julia/packages/Makie/rEu75/src/interaction/inspector.jl:301 [inlined]
│      [6] (::Makie.var"#1312#1316"{Makie.DataInspector})(::Tuple{Float64, Float64})
│        @ Makie ~/.julia/packages/Makie/rEu75/src/interaction/inspector.jl:281
│      [7] #invokelatest#2
│        @ ./essentials.jl:892 [inlined]
│      [8] invokelatest
│        @ ./essentials.jl:889 [inlined]
│      [9] notify
│        @ ~/.julia/packages/Observables/YdEbO/src/Observables.jl:206 [inlined]
│     [10] setindex!(observable::Observables.Observable, val::Any)
│        @ Observables ~/.julia/packages/Observables/YdEbO/src/Observables.jl:123
│     [11] showmetadata(fig::Makie.Figure, ax::Makie.Axis, p::MakieCore.Plot{QuantumSavory.registernetplot, Tuple{RegisterNet}}, reg::Int64, slot::Int64)
│        @ QuantumSavoryMakie ~/.julia/dev/QuantumSavory/ext/QuantumSavoryMakie/QuantumSavoryMakie.jl:357
│     [12] top-level scope
│        @ visualizations.md:71
│     [13] eval
│        @ ./boot.jl:385 [inlined]
│     [14] #58
│        @ ~/.julia/packages/Documenter/qoyeC/src/expander_pipeline.jl:754 [inlined]
│     [15] cd(f::Documenter.var"#58#60"{Module, Expr}, dir::String)
│        @ Base.Filesystem ./file.jl:112
│     [16] (::Documenter.var"#57#59"{Documenter.Page, Module, Expr})()
│        @ Documenter ~/.julia/packages/Documenter/qoyeC/src/expander_pipeline.jl:753
│     [17] (::IOCapture.var"#5#9"{DataType, Documenter.var"#57#59"{Documenter.Page, Module, Expr}, IOContext{Base.PipeEndpoint}, IOContext{Base.PipeEndpoint}, Base.TTY, Base.TTY})()
│        @ IOCapture ~/.julia/packages/IOCapture/Y5rEA/src/IOCapture.jl:170
│     [18] with_logstate(f::Function, logstate::Any)
│        @ Base.CoreLogging ./logging.jl:515
│     [19] with_logger
│        @ ./logging.jl:627 [inlined]
│     [20] capture(f::Documenter.var"#57#59"{Documenter.Page, Module, Expr}; rethrow::Type, color::Bool, passthrough::Bool, capture_buffer::IOBuffer, io_context::Vector{Any})
│        @ IOCapture ~/.julia/packages/IOCapture/Y5rEA/src/IOCapture.jl:167
│     [21] runner(::Type{Documenter.Expanders.ExampleBlocks}, node::MarkdownAST.Node{Nothing}, page::Documenter.Page, doc::Documenter.Document)
│        @ Documenter ~/.julia/packages/Documenter/qoyeC/src/expander_pipeline.jl:752
└ @ Documenter ~/.julia/packages/Documenter/qoyeC/src/utilities/utilities.jl:44

But there are no issues when the code is run independently of the doc build