Allow users to pass custom trusted certs

**What would you like to be added**:
Allow users to pass custom certs through the cluster config and install/trust them on the bootstrap and workload clusters.

**Why is this needed**:
There are cases where the network can intercept the certs and replace them with a custom trusted cert. It will be good to have the ability to trust these certs for users who have this setup.

The issue identifies cluster configuration and bootstrap and workload clusters as the affected entry points. Start by locating the configuration and cluster setup paths, then determine how custom certificates should be installed and trusted in both cluster types. Done means users can provide certificates through cluster config and both clusters trust them.

Written by the indexing model from the issue text.