Don't merge prop names in different categories

When importing a few files, any prop names that repeat will be overwritten.

The Issue

Given a set of files:

# margins.yml

props:
  - name: auto
    value: auto
  - name: px
    value: 1px
  - name: 1
    value: 0.25rem

global:
  category: margins
  type: length


# paddings.yml

props:
  - name: px
    value: 1px
  - name: 1
    value: 0.25rem

global:
  category: paddings
  type: length


# dimensions.yml

imports:
  - "./margins.yml"
  - "./paddings.yml"

Expected Output

When converting dimensions.yml, using a slightly modified map.scss format that groups by cateogry instead of file-name, I expect to see:

// spacings.scss

$margins: (
    'auto': (auto),
    'px': (1px),
    '1': (0.25rem)
);

$paddings: (
    'px': (1px),
    '1': (0.25rem)
);

Actual Output

Instead I'm seeing:

// spacings.scss

$margins: (
    'auto': (auto)
);

$paddings: (
    'px': (1px),
    '1': (0.25rem)
);

In other words, the repeated prop names ("px" and "1") are omitted from the $margins map.

Rationale

Since I'm using SCSS maps, I don't need to prefix the name of the token with the category, however this means that between categories I am reusing the same name.

I can confirm this is happening. Will take a look