Added new section (#26554)
Added new section (#26554)

* Added new section

Added a new section for defining what can be returned in custom methods and how to correct a mistake with returns

* Update guide/english/csharp/return/index.md

Co-Authored-By: marcusparsons <ba511086d201680a19ca38858092409269062cc4@users.noreply.github.com>

* Update guide/english/csharp/return/index.md

Co-Authored-By: marcusparsons <ba511086d201680a19ca38858092409269062cc4@users.noreply.github.com>

* Update guide/english/csharp/return/index.md

Co-Authored-By: marcusparsons <ba511086d201680a19ca38858092409269062cc4@users.noreply.github.com>

* Update guide/english/csharp/return/index.md

Co-Authored-By: marcusparsons <ba511086d201680a19ca38858092409269062cc4@users.noreply.github.com>

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