2.0: Rename `Iterators.repeated`

[jariji]

I find the difference between "repeat" and "repeated" hard to remember.

julia> repeat([1,2], 3)
6-element Vector{Int64}:
 1
 2
 1
 2
 1
 2

julia> collect(Iterators.repeated([1,2], 3))
3-element Vector{Vector{Int64}}:
 [1, 2]
 [1, 2]
 [1, 2]

#47354 proposed Iterators.cycle(itr, n) for the lazy version of repeat(itr, n).

[vtjnash]

Just as an observation in general: we might add aliases now for something like this, but we are unlikely to remove or rename functions in 2.0 unless the old one was functionally broken or deficient in some way

[mcabbott]

Can you specify what names you would prefer for Iterators.repeated(itr, n) and Iterators.repeated(itr)?