Android stores client certificates are not used by Element app for reverse proxy authentication

### Steps to reproduce

1. Configure a Synapse-Matrix homeserver behind an nginx reverse-proxy.
> cat /etc/nginx/sites-available/matrix
```
...
ssl_certificate /home/user/matrix/matrix-server.crt;
ssl_certificate_key /home/user/matrix/matrix-server.key;
ssl_client_certificate /home/user/easy-rsa/pki/ca.crt;
ssl_verify_client on;
...
```
2. Import root AC and client certificate in the android store :


3. In the server selection, when select the homeserver and press next.

.

Client certificate authentication is a very interesting security measure as it completly blocks the access to the server behind the reverse proxy to unauthorized devices and I don't think we are the only people that needs / use this so it could be interesting to fix this behavior.

### Outcome

#### What did you expect?
If a client certificate is imported on the Windows operating system certificate store it is automatically used by the element desktop app.


I expect the android app to use the client certificate from the system store like the desktop app.

#### What happened instead?


### Your phone model

One plus 10 Pro and Galaxy A50

### Operating system version

11 and 12

### Application version and app store

1.5.34 and 1.5.32

### Homeserver

synapse matrix homeserver 1.53

### Will you send logs?

Yes

### Are you willing to provide a PR?

No