fix indexing for OneTo on v1.7

[jishnub]

With JuliaLang/julia#40997 now merged and available on v1.7.0-beta2, we don't need to define indexing for OneTo with IdentityUnitRange in this package. This reduces type-piracy, and also doesn't overwrite the method from Base.

Also remove deprecated UnionAll declarations in Varrag in no_offset_view.

Tests now pass with --depwarn=error

[codecov]

Codecov Report

Merging #249 (6aa8218) into master (4bd33fb) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #249      +/-   ##
==========================================
+ Coverage   95.26%   95.28%   +0.02%     
==========================================
  Files           5        5              
  Lines         422      424       +2     
==========================================
+ Hits          402      404       +2     
  Misses         20       20              

Impacted Files	Coverage Δ
src/OffsetArrays.jl	98.23% <100.00%> (+0.01%)	⬆️

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[johnnychen94]

This PR actually solves two warnings:

Before:

$julia-1.7 --depwarn=error --project=.

julia> using OffsetArrays
[ Info: Precompiling OffsetArrays [6fe1bfb0-de20-5000-8ca7-80f57d26f881]
WARNING: Method definition getindex(Base.OneTo{T} where T<:Integer, Base.IdentityUnitRange{var"#s1"} where var"#s1"<:(Base.AbstractUnitRange{var"#s2"} where var"#s2"<:Integer)) in module Base at indices.jl:405 overwritten in module OffsetArrays at /Users/jc/Documents/Julia/OffsetArrays.jl/src/OffsetArrays.jl:513.
  ** incremental compilation may be fatally broken for this module **

ERROR: LoadError: Wrapping `Vararg` directly in UnionAll is deprecated (wrap the tuple instead).

Edit:

Oh, you already mentioned the Vararg deprecation :)