Fix %%sql cells in %run_shared magic

Author: kesmit13

singlestoredb/magics/run_shared.py

@@ -113,13 +113,15 @@ def get_cells() -> Any:
         with prepended_to_syspath(dname):
             try:
                 for cell in get_cells():
-                    result = self.run_cell(cell, silent=True, shell_futures=shell_futures)
+                    result = self.shell.run_cell(
+                        cell, silent=True, shell_futures=shell_futures,
+                    )
                     if raise_exceptions:
                         result.raise_error()
                     elif not result.success:
                         break
             except Exception:
                 if raise_exceptions:
                     raise
-                self.showtraceback()
+                self.shell.showtraceback()
                 warn('Unknown failure executing file: <%s>' % fpath)