Save component metadata in `spec` column

What does this MR do and why?

We've been saving CI components inputs metadata in a column named inputs, but when we introduce CI steps we'll also need to save outputs.

In !146674 (merged), we introduced a spec column that will contain the entire spec value for all CI component types. This MR updates the code to save to the spec column instead of inputs. It also updates the GraphQL code to fetch the inputs data first from spec, and then from inputs if spec is nil.

Issue: #443662 (closed)