[lldb] Remove prefer-dynamic-value test override

[lldb] Remove prefer-dynamic-value test override

Remove the test override of `target.prefer-dynamic-value`.

Previously, the lldb default was `no-dynamic-values`. In rG9aa7e8e9ffbe (in
2015), the default was changed to `no-run-target`, but at that time the tests
were changed to be run with `no-dynamic-value`. I don't know the reasons for
not changing the tests, perhaps to avoid determining which tests to change, and
what about them to change.

Because `no-run-target` is the lldb default, I think it makes sense to make it
the test default too. It puts the test config closer to what's used in
practice.

This change removes the `target.prefer-dynamic-value` override, and for those
tests that failed, they have been updated to explicitly use
`no-dynamic-values`. Future changes could update these tests to use dynamic
values too, or they can be left as is to exercise non-dynamic typing.

Differential Revision: https://reviews.llvm.org/D132382