method ambiguity in julia 11r4

In julia 11.0r4
```julia
using Test, LaTeXStrings

detect_ambiguities(Base, Core, LaTeXStrings; recursive=true)
```

```
Skipping Base.cwstring
1-element Vector{Tuple{Method, Method}}:
 (write(io::IO, s::LaTeXString) @ LaTeXStrings ~/.julia/packages/LaTeXStrings/ZtSdh/src/LaTeXStrings.jl:94, write(io::Base.AnnotatedIOBuffer, x::AbstractString) @ Base strings/annotated.jl:491)

```