[lldb/Utility] Fix layering violation caused by ScriptedMetadata

This patch moves `ScriptedMetadata.h` from the `Interpreter` directory to
the `Utility` sub-directory since `ProcessInfo.h` depends on it.

It also gets rid of the unused `OptionGroupPythonClassWithDict`
constructor for `ScriptedMetadata` which would address the layering
violation.

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>