allowReflectiveAutoCloneType must work outside of Builder context

[jackkoenig]

Some 2.11 tests caught this issue in #1810 since they don't run with the plugin.
Because this is already fixed there, this PR doesn't need backporting.

Basically, the problem is that the check I added in #1804 for disabling reflective autoclonetype triggers if reflective autoclonetype happens outside of a Builder context. This changes makes Builder.allowReflectiveAutoCloneType succeed if there is no DynamicContext. Because allowReflectiveAutoCloneType is only used in testing, this is the correct thing to do.

Contributor Checklist

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As a bug fix to a not-yet-released feature, no release notes for this particular PR

Type of Improvement

• bug fix

API Impact

No impact

Backend Code Generation Impact

No impact

Desired Merge Strategy

• Squash

Release Notes

Reviewer Checklist (only modified by reviewer)

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[ducky64]

lgtm