Add a missing author for the task mult_data_wrangling
Add a missing author for the task mult_data_wrangling

As approved by Jascha Sohl-Dickstein, I add the missing author Lidia Contreras-Ochando from the task mult_data_wrangling, as it can be checked in the task page https://github.com/google/BIG-bench/tree/main/bigbench/benchmark_tasks/mult_data_wrangling
google/BIG-bench,google/BIG-bench