feat(loading-bar): export LoadingBarApi (#354)

* 对外导出 LoadingBarApiInjection

* changlog

* change log  export  type

* 修改为LoadingBarApi

* Apply suggestions from code review

* Update CHANGELOG.en-US.md

Co-authored-by: hhf <1170533231@qq.com>
Co-authored-by: 07akioni <07akioni2@gmail.com>

CHANGELOG.en-US.md

@@ -1,5 +1,11 @@
 # CHANGELOG
 
+## Pending
+
+### Feats
+
+- `n-loading-bar` export `LoadingBarApi` type
+
 ## 2.15.2 (2021-07-02)
 
 ### Feats

CHANGELOG.zh-CN.md

@@ -1,5 +1,11 @@
 # CHANGELOG
 
+## Pending
+
+### Feats
+
+- `n-loading-bar` 导出 `LoadingBarApi` 类型
+
 ## 2.15.2 (2021-07-02)
 
 ### Feats

src/loading-bar/index.ts

@@ -1,6 +1,7 @@
 export { default as NLoadingBarProvider } from './src/LoadingBarProvider'
 export type {
   LoadingBarProviderInst,
-  LoadingBarProviderProps
+  LoadingBarProviderProps,
+  LoadingBarApiInjection as LoadingBarApi
 } from './src/LoadingBarProvider'
 export { useLoadingBar } from './src/use-loading-bar'