Use unique container names for Docker executor

What does this MR do?

Makes the names of containers created by Docker executor uniq for each job.

Why was this MR needed?

Trying to find out the root cause of #4327 (closed) we've decided to make the container names uniq (excluding the cache containers for now).

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?

Closes #4327 (closed)

Related to #4515