[bug-fix] Increase 3dballhard and GAIL default steps (#3636) (#3647)

Co-authored-by: Ervin T <ervin@unity3d.com>

config/gail_config.yaml

     hidden_units: 128
     lambd: 0.95
     learning_rate: 3.0e-4
-    max_steps: 5.0e4
+    max_steps: 5.0e5
     memory_size: 256
     normalize: false
     num_epoch: 3

config/trainer_config.yaml

     buffer_size: 12000
     summary_freq: 12000
     time_horizon: 1000
-    max_steps: 5.0e5
+    max_steps: 5.0e6
     beta: 0.001
     reward_signals:
         extrinsic: