Description: Unable to use Hashicorp Vault's new Integrated Storage (Raft) Backend due to the packaged vault.service not only setting ProtectHome=read-only but also ProtectSystem=full preventing Vault from storing its data in its home directory, nor anywhere else (e.g. /etc/vault/).

Additional info:
* package version(s)
vault 1.13.2-1

* config and/or log files etc.
NA - Issue resides in package contents (vault.service)

* link to upstream bug report, if any
NA - Issue is in our package

Steps to reproduce:

1. Install vault
2. Create /etc/vault.hcl with the Raft storage method with Raft storage

```
storage "raft" {
path = "./data"
node_id = "node1"
}
```

3. Watch vault fail vaguely about a read only filesytem, but su'ing as the user and running it starts up fine.

4. Notice the contents of vault.service making it a read-only process despite needing to write its own storage in this mode.


In the meantime the workaround is to add a patch in our IaC to comment out that protection. I can understand how it were initially used given Vault had to rely on external services for its secret object storage. But with raft, Vault can handle itself but needs write access to *something* (Preferably its home at /var/lib/vault).