Move StringMappedTypeSerialisationTest out of backend tck

Description

This test relies on the fact that some specific types are converted to String. But that's not the case for all as a backend can overrideTypes.
So this test should only be run on the Map backend.

Environment

None

Assignee

Jonathan Halliday

Reporter

Emmanuel Bernard

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Feedback Requested

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Feedback Requested By

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backPortable

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Suitable for new contributors

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backportDecision

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backportReEvaluate

None

Components

Fix versions

Priority

Critical
Configure