[lldb/Plugins] Move ScriptedThreadInterface to ScriptedThread

Since we can have multiple Scripted Threads per Scripted Process, having
only a single ScriptedThreadInterface (with a single object instance)
will cause the method calls to be done on the wrong object.

Instead, this patch creates a separate ScriptedThreadInterface for each
new lldb_private::ScriptedThread to make sure we interact with the right
instance.

rdar://87427911

Differential Revision: https://reviews.llvm.org/D117070

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

lldb/source/Plugins/ScriptInterpreter/Python/ScriptedProcessPythonInterface.h

@@ -57,7 +57,7 @@ public:
   llvm::Optional<std::string> GetScriptedThreadPluginName() override;
 
 private:
-  lldb::ScriptedThreadInterfaceSP GetScriptedThreadInterface() override;
+  lldb::ScriptedThreadInterfaceSP CreateScriptedThreadInterface() override;
 };
 } // namespace lldb_private