v6.8.1

This patch release fixes the `Exception in ASGI application` startup error that prevents Invoke from starting.

> The error was introduced by an upstream dependency (fastapi). We've pinned the fastapi dependency to the last known working version.

## Installing and Updating

**The Invoke Launcher is the recommended way to install, update and run Invoke**. It takes care of a lot of details for you - like installing the right version of python - and runs Invoke as a desktop application.

Note: With recent updates to `torch`, users on older GPUs (20xx and 10xx series) will likely run into issues with installing/updating. We are still evaluating how we can support older GPUs, but in the meantime users have found success manually downgrading `torch`. Head over to [discord](https://discord.gg/ZmtBAhwWhy) if you need help.

Follow the [Quick Start guide](https://invoke-ai.github.io/InvokeAI/installation/quick_start/) to get started with the launcher.

If you don't want to use the launcher, or need a headless install, you can follow the [manual install guide](https://invoke-ai.github.io/InvokeAI/installation/manual/).

## What's Changed
* Fix(nodes): color correct invocation by @dunkeroni in https://github.com/invoke-ai/InvokeAI/pull/8605


**Full Changelog**: https://github.com/invoke-ai/InvokeAI/compare/v6.8.0...v6.8.1