Array tutorial (#60557)
Modify the indexing section in the manual for Arrays to make it more
like a tutorial. The related discussion for this is in -
https://discourse.julialang.org/t/comprehensive-intermediate-level-array-tutorial/134683/12
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Co-authored-by: Patrick Häcker <pat_h@web.de>
Co-authored-by: Max Horn <max@quendi.de>
Co-authored-by: matthias314 <56549971+matthias314@users.noreply.github.com>
Co-authored-by: Andy Dienes <51664769+adienes@users.noreply.github.com>
Co-authored-by: Shuhei Kadowaki <40514306+aviatesk@users.noreply.github.com>
