Add support for a map of labels in the flow validator

[anna-geller]

Feature description

We want to support both options for the definition of labels.

1. A list of key-value pairs:

id: myflow
namespace: dev
labels:
  - key: team
    value: data
  - key: project
    value: dwh

2. A map of labels:

id: myflow
namespace: dev
labels:
  team: data
  project: dwh

Initially, option 2 was the default.
Now, option 1 is the default and the validator complains when using the Map syntax.

Both work, but the validator currently only accepts the first option.

Both options are valid. This issue is to bring back support for the Map of labels on the schema for both web validator and VS Code extension.

[loicmathieu]

We can support both but in this case the validator will not be aware of the Label type anymore so it will validate any arrays.

Using a map will works

labels:
  key: value

Using a list of labels will work

labels:
  - key: key
    value: value1

The following will validate but create an invalid label in the database (not that it will not crash even at validation time)

labels:
  - toto: titi