Add timeout when sending request for certificate

What does this MR do?

Adds a timeout when sending a request to fetch a certificate.

Why was this MR needed?

The default http client doesn't have a timeout, so requests can hang indefinitely.

Are there points in the code the reviewer needs to double check?

Does this MR meet the acceptance criteria?

• Documentation created/updated
• Added tests for this feature/bug
• In case of conflicts with master - branch was rebased

What are the relevant issue numbers?

Related to #4827 (closed)