Add restart solution files for unsteady pitching and plunging test cases (#190)

- pitching_naca64a010_euler: solution_flow_00000.csv and 00001.csv
  from t=98 and t=99 of 100-step Euler run
- pitching_naca64a010_rans: solution_flow_00000.csv and 00001.csv
  from t=89 and t=90 of RANS/SA run
- plunging_naca0012: solution_flow_00000.csv and 00001.csv
  from t=98 and t=99 of 100-step plunging run

Co-authored-by: Pedro Gomes <38071223+pcarruscag@users.noreply.github.com>

Author: Sahilll10