Allow using a custom Hub with SentryTraced for Jetpack Compose

### Problem Statement

I would like to provide my own `Hub` when using the `SentryTraced` composable.

Currently, the default SentryTraced composable relies on the top-level static `Sentry` object for fetching the current transaction (by way of the `getRootSpan()` function), which can be limiting for users who wish to utilize a custom hub. This limitation can lead to potential issues when attempting to manage multiple Sentry/`Hub` instances or when needing to apply custom configurations to individual instances.

### Solution Brainstorm

Some potential solutions could be:
- Allowing a `Hub` to be passed in to the composable
- Allowing a `Transaction` to be passed in to the composable