Improve naming and referencing of pods

Summary

• Each CTA-related pod now has the cta- prefix, making it consistent with what the EOS Helm chart will have. This also allows for easy distinction between what belongs to CTA in a given namespace
  • The ctaeos has not been renamed on purpose, as this will be replaced by the EOS Helm chart soon
• The tests now have a better distinction for the eosinstance: EOS_MGM_HOST, EOS_INSTANCE_NAME, and EOS_MGM_POD. While these currently all have the value ctaeos, this will not be the case in the future
• The pod names used in the test scripts are stored in variables, and each pod (except for eos) specifies the container. This makes it easier to update pod names, and makes sure that the correct container is always selected if any of the pods get more containers in the future (e.g. init containers).
• Removed the namespace from the helm release name
• Fixed a few deprecated backticks

Additional Required Actions

• Requires manual tests in pre-production: YES/NO
• Requires a documentation update: YES/NO

References

Closes #1008 (closed)