fix api version of unitUsage option

Signed-off-by: Nsunyaozu <sunyaozu@huawei.com>

zh-cn/application-dev/reference/apis/js-apis-intl.md

@@ -388,7 +388,7 @@ resolvedOptions(): NumberOptions
 | currencyDisplay          | string  | 是    | 是    | 货币的显示方式，取值包括："symbol", "narrowSymbol", "code", "name"。 |
 | unit                     | string  | 是    | 是    | 单位名称，如："meter"，"inch"，“hectare”等。        |
 | unitDisplay              | string  | 是    | 是    | 单位的显示格式，取值包括："long", "short", "narrow"。 |
-| unitUsage                | string  | 是    | 是    | 单位的使用场景，取值包括："default", "area-land-agricult", "area-land-commercl", "area-land-residntl", "length-person", "length-person-small", "length-rainfall", "length-road", "length-road-small", "length-snowfall", "length-vehicle", "length-visiblty", "length-visiblty-small", "length-person-informal", "length-person-small-informal", "length-road-informal", "speed-road-travel", "speed-wind", "temperature-person", "temperature-weather", "volume-vehicle-fuel"。 |
+| unitUsage<sup>8+</sup>                | string  | 是    | 是    | 单位的使用场景，取值包括："default",&nbsp;"area-land-agricult",&nbsp;"area-land-commercl",&nbsp;"area-land-residntl",&nbsp;"length-person",&nbsp;"length-person-small",&nbsp;"length-rainfall",&nbsp;"length-road",&nbsp;"length-road-small",&nbsp;"length-snowfall",&nbsp;"length-vehicle",&nbsp;"length-visiblty",&nbsp;"length-visiblty-small",&nbsp;"length-person-informal",&nbsp;"length-person-small-informal",&nbsp;"length-road-informal",&nbsp;"speed-road-travel",&nbsp;"speed-wind",&nbsp;"temperature-person",&nbsp;"temperature-weather",&nbsp;"volume-vehicle-fuel"。 |
 | signDisplay              | string  | 是    | 是    | 数字符号的显示格式，取值包括："auto",&nbsp;"never",&nbsp;"always",&nbsp;"expectZero"。 |
 | compactDisplay           | string  | 是    | 是    | 紧凑型的显示格式，取值包括："long",&nbsp;"short"。      |
 | notation                 | string  | 是    | 是    | 数字的格式化规格，取值包括："standard",&nbsp;"scientific",&nbsp;"engineering",&nbsp;"compact"。 |