LOG_REQUEST_HEADERS (#5143)

# What this PR does

Adds a separate env variable for logging headers and sets it to false by
default.

## Checklist

- [ ] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

engine/settings/base.py

@@ -384,7 +384,8 @@ MIDDLEWARE = [
     "apps.user_management.middlewares.OrganizationDeletedMiddleware",
 ]
 
-if OTEL_TRACING_ENABLED:
+LOG_REQUEST_HEADERS = getenv_boolean("LOG_REQUEST_HEADERS", default=False)
+if LOG_REQUEST_HEADERS:
     MIDDLEWARE.insert(0, "engine.middlewares.LogRequestHeadersMiddleware")
 
 LOG_REQUEST_ID_HEADER = "HTTP_X_CLOUD_TRACE_CONTEXT"