sage.misc.sage_input: Remove import from sage.all

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Component: **refactoring**

Author: **Matthias Koeppe**

Branch/Commit: **[`73f4ab7`](https://github.com/sagemath/sagetrac-mirror/commit/73f4ab79d35ee3c92079f1a4e9b801b4db3bb709)**

Reviewer: **Frédéric Chapoton**

_Issue created by migration from https://trac.sagemath.org/ticket/33801_

