Coercion from ChartFunctionRing to ScalarFieldAlgebra

[mjungmath]

In some doctests, a coercion from the ring of chart functions to the algebra of scalar fields is used. However, it is not officially populated yet. In this ticket, I add this specific coercion.

CC: @egourgoulhon @tscrim

Component: geometry

Keywords: chart_function, scalar_field

Author: Michael Jung

Branch/Commit: 385c4f9

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/30112

[mjungmath]

Branch: u/gh-mjungmath/coercion_from_chartfunction_to_scalarfield

[mjungmath]

Commit: 8b98301

[mjungmath]

New commits:

8b98301

Trac #30112: coerce map from chart function ring added

[mjungmath]

Changed keywords from none to chart_function, scalar_field

[mjungmath]

Author: Michael Jung

[mjungmath]

Description changed:

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+In some doctests, a coercion from the ring of chart functions to the algebra of scalar fields is used. However, it is not officially populated yet. In this ticket, I add this specific coercion.