MvNormal(d::Int, σ::Real) is deprecated

[haakon-e]

When running tests locally, I get the following warning:

Starting tests for TOMLInterface
┌ Warning: `MvNormal(d::Int, σ::Real)` is deprecated, use `MvNormal(LinearAlgebra.Diagonal(FillArrays.Fill(σ ^ 2, d)))` instead.
│   caller = ip:0x0
└ @ Core :-1
Completed tests for TOMLInterface, 4 seconds elapsed

I'm not quite sure where this warning is coming from. The log suggests in the tests for TOMLInterface, but I can't seem to find the offending line.

[odunbar]

I think it is here in the test parameter example.
https://github.com/CliMA/EnsembleKalmanProcesses.jl/blob/79057eb73957b7a7a072ecfb8f6cb98a81ab5a17/test/TOMLInterface/toml/uq_test_parameters.toml#L12C1-L15

I think we will soon be doing a refresh of this interface and so will hopefully clear this issue at that time.