feat: upgrade to NGO v1.8.1, conversion to universal Rpcs, utility assembly includes Unity.Collections [MTT-8188]

[fernando-cortez]

Description

This PR upgrades to Netcode for GameObjects v1.8.1, and also upgrades the Rpcs used inside the project to the newer API, Universal Rpcs.

Note: along the way, I've had to modify ClientConnectedState. A recent commit to Netcode for GameObjects has added this change to a host/server's disconnect logic:

• Basically, when you shutdown a server/host during an in-progress network session the server/host will send disconnect messages and will wait for a period of time for all connected clients to disconnect or if it times out it will just finalize the shutdown sequence.

Where a connected client had previously assumed that a host's disconnect would produce an empty DisconnectReason string, we now have one sent to disconnected clients. This string has appropriately been checked against inside ClientConnectedState, which fixed a failing test (due to the assumption listed).

Issue Number(s)

MTT-8188

Contribution checklist

• Tests have been added for boss room and/or utilities pack
• Release notes have been added to the project changelog file and/or package changelog file
• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• JIRA ticket ID is in the PR title or at least one commit message
• Include the ticket ID number within the body message of the PR to create a hyperlink
• An Index entry has been added in readme.md if applicable

[unity-cla-assistant]

All committers have signed the CLA.

[NoelStephensUnity]

Left one comment that should apply to all updated Rpcs.

[NoelStephensUnity]

Looks good to me!