CLDR-17367 cldr-json: put unitPrefixes into units.json

[srl295]

• data from CLDR-16939

CLDR-17367

• This PR completes the ticket.

extract from cldr-json/cldr-core/supplemental/units.json:

{
  "supplemental": {
    "version": {
      "_unicodeVersion": "15.1.0",
      "_cldrVersion": "45"
    },
    "unitPrefixes": {
      "atto": {
        "_symbol": "a",
        "_power10": "-18"
      },
      "centi": {
        "_symbol": "c",
        "_power10": "-2"
      },
      "deci": {
        "_symbol": "d",
        "_power10": "-1"
      },
      "deka": {
        "_symbol": "da",
        "_power10": "1"
      },
      "exa": {
        "_symbol": "E",
        "_power10": "18"
      },

ALLOW_MANY_COMMITS=true

[srl295]

(structure matches other unit json files.)

[sffc]

CC @younies -- PTAL at the new JSON and if you can use it in ICU4X