[BUG] Net Spec Keys is overwritten in MADDPG

[EdanToledo]

Describe the bug

In the MADDPG system, regardless of the net spec keys given to the network_factory (i.e create_default_networks), the system overwrites these values. This causes issues when trying to give different networks to different agents. This issue occurs on line 318 and 449.

To Reproduce

Steps to reproduce the behavior:

1. Input any non-standard net_spec_keys to the create default network method
2. Witness that the inputted value is not carried over

Expected behavior

The given net_spec_keys should be used otherwise the default values should be constructed.

Context (Environment)

• Latest Mava
• Ubuntu Linux

Additional context

Haven't inspected other classes, might only be present in MADDPG.

Possible Solution

Somehow check for given value - not sure if this is possible. Maybe make net_spe_keys a parameter to the system instead of the network factory.