revert changes to 20 bullets

Project/Assets/Bullet/Prefabs/BulletArea.prefab

     - target: {fileID: 5260467540845178092, guid: 16266ae2c040142b1a996878d94ec3fb,
         type: 3}
       propertyPath: MaxNumObservables
-      value: 40
+      value: 20
       objectReference: {fileID: 0}
     m_RemovedComponents:
     - {fileID: 9204493211719777360, guid: 16266ae2c040142b1a996878d94ec3fb, type: 3}

Project/Assets/Bullet/Scripts/DodgeAgent.cs

 
         foreach (Bullet b in bullets)
         {
-            if (numBulletAdded >= 40)
+            if (numBulletAdded >= 20)
             {
                 break;
             }

ml-agents/mlagents/trainers/torch/networks.py

             #     self.h_size
             #     )
             self.entity_embedding = EntityEmbeddings(
-                x_self_len, entities_sizes, [40], self.n_embd  # , concat_self=False
+                x_self_len, entities_sizes, [20], self.n_embd  # , concat_self=False
-            self.transformer = ResidualSelfAttention(self.n_embd, [40])
+            self.transformer = ResidualSelfAttention(self.n_embd, [20])
             # self.transformer = SmallestAttention(x_self_len, entities_sizes, self.h_size, self.h_size)
             # self.transformer = SmallestAttention(64, [64], self.h_size, self.h_size)
             # self.use_fc = True