Remove existing circuit breaker

Breaking change: we have removed the circuit breaker from connection attempts. Consumers should now implement this externally.

• Merge pull request #43 from bbc/IPLAYER-45836-cache-circuit-breaker fd6a1ca
• chore: removed unused function ca9afc6
• chore: remove levee dependency f2f4065
• feat: remove unnecessary circuit breaker 09f2fd8

v4.4.0...v5.0.0