Normalize indices in promote_shape error messages (#41311)
Seeing implementation details like `Base.OneTo` in error messages may
be confusing to some users (cf discussion in #39242,
[discourse](https://discourse.julialang.org/t/promote-shape-dimension-mismatch/57529/)).
This PR turns
```julia
julia> ones(2, 3) + ones(3, 2)
ERROR: DimensionMismatch("dimensions must match: a has dims (Base.OneTo(2), Base.OneTo(3)), b has dims (Base.OneTo(3), Base.OneTo(2)), mismatch at 1")
```
into
```julia
julia> ones(2, 3) + ones(3, 2)
ERROR: DimensionMismatch("dimensions must match: a has size (2, 3), b has size (3, 2), mismatch at 1")
```
Fixes #40118.
(This is basically #40124, but redone because I made a mess rebasing).
---------
Co-authored-by: Jameson Nash <vtjnash@gmail.com>
