Fix linear indexing for ReshapedArray if the parent has offset axes (#41232)
This PR fixes
```julia
julia> r = reshape(Base.IdentityUnitRange(3:4), 2, 1)
2×1 reshape(::Base.IdentityUnitRange{UnitRange{Int64}}, 2, 1) with eltype Int64:
3
4
julia> collect(r) == r
false
julia> collect(r)
2×1 Matrix{Int64}:
3258125826116431922
3688512103538242609
```
After this PR,
```julia
julia> collect(r)
2×1 Matrix{Int64}:
3
4
```