Remove eigvecs

The easiest implementation would just be a wrapper around `eigen`, and
this should await some more experiments with the eigenvector gauge
fixing.

src/tensors/factorizations.jl

@@ -190,28 +190,6 @@ function LinearAlgebra.eigvals!(t::TrivialTensorMap; kwargs...)
     return LinearAlgebra.eigvals!(t.data; kwargs...)
 end
 
-function LinearAlgebra.eigvecs(t::AbstractTensorMap; kwargs...)
-    InnerProductStyle(t) === EuclideanProduct() || throw_invalid_innerproduct(:eigvecs)
-    domain(t) == codomain(t) ||
-        throw(SpaceMismatch("`eigvecs` requires domain and codomain to be the same"))
-    S = spacetype(t)
-    I = sectortype(t)
-    A = storagetype(t)
-    Vdata = SectorDict{I,A}()
-    dims = SectorDict{I,Int}()
-    for (c, b) in blocks(t)
-        vectors = LinearAlgebra.eigvecs(b; kwargs...)
-        Vdata[c] = vectors
-        dims[c] = size(vectors, 2)
-    end
-    if length(domain(t)) == 1
-        W = domain(t)[1]
-    else
-        W = S(dims)
-    end
-    return TensorMap(Vdata, domain(t) ← W)
-end
-
 """
     eig(t::AbstractTensor, (leftind, rightind)::Index2Tuple; kwargs...) -> D, V