move argo workflows to ci/cd tab. remove unused components

[nabuskey]

This moves Argo Workflows related components to the CI/CD tab. Previously the components were under the Overview tab. Generally speaking, CI tools should go under the CI/CD tab when representing applications / components in Backstage.

This also removes components that were not used but present in the overview tab.

Before:

After:

fixes: #35

[omrishiv]

I'm a little removed from this code and I'm not entirely sure what the purpose of the change is. Can we add it to the description so we know what we're trying to accomplish?

[omrishiv]

I see it now, thanks! This looks good