chore: add isBool

Author: Simon he

src/index.ts

@@ -22,5 +22,6 @@ export { isNaN } from './isNaN'
 export { isSymbol } from './isSymbol'
 export { isNull } from './isNull'
 export { isReg } from './isReg'
+export { isBool } from './isBool'
 export { VFetch } from './VFetch'
 export { interceptError } from './interceptError'

src/isBool.ts

@@ -0,0 +1,3 @@
+export function isBool(value: any): boolean {
+  return typeof value === 'boolean'
+}