[BUG] Add headers to async client requests (#3236)

## Description of changes

*Summarize the changes made by this PR.*
 - Improvements & Bug fixes
- Fixes bug where headers were not being added to async client requests.
Also adds the verify argument.
 - New functionality
   - ...

## Test plan
*How are these changes tested?*

- [ ] Tests pass locally with `pytest` for python, `yarn test` for js,
`cargo test` for rust

## Documentation Changes
*Are all docstrings for user-facing APIs updated if required? Do we need
to make documentation changes in the [docs
repository](https://github.com/chroma-core/docs)?*

Author: drewkim

chromadb/api/async_fastapi.py

@@ -106,7 +106,11 @@ def _get_client(self) -> httpx.AsyncClient:
             loop_hash = 0
 
         if loop_hash not in self._clients:
-            self._clients[loop_hash] = httpx.AsyncClient(timeout=None)
+            self._clients[loop_hash] = httpx.AsyncClient(
+                timeout=None,
+                headers=self._settings.chroma_server_headers,
+                verify=self._settings.chroma_server_ssl_verify or False,
+            )
 
         return self._clients[loop_hash]