feat(api): add gzip middleware

On our local installs this will be a very minor change. For those running on remote servers, load times should be slightly improved.

It's a small change but I think correct.

invokeai/app/api_app.py

@@ -17,6 +17,7 @@ if True:  # hack to make flake8 happy with imports coming after setting up the c
     import uvicorn
     from fastapi import FastAPI
     from fastapi.middleware.cors import CORSMiddleware
+    from fastapi.middleware.gzip import GZipMiddleware
     from fastapi.openapi.docs import get_redoc_html, get_swagger_ui_html
     from fastapi.openapi.utils import get_openapi
     from fastapi.staticfiles import StaticFiles
@@ -72,6 +73,8 @@ app.add_middleware(
     allow_headers=app_config.allow_headers,
 )
 
+app.add_middleware(GZipMiddleware, minimum_size=1000)
+
 
 # Add startup event to load dependencies
 @app.on_event("startup")