Rename remaining classes that operate on integrations to use the word "integration" instead of "service"
This issue was created from this discussion !61210 (comment 572784548).
This issue is to:
- Rename all other classes that operate on integrations to use the word integration instead of service in its name. (See #330670 (comment 575341780) although there may be more).
- Where possible these classes should be namespaced in