docs: prefer const

Author: brettz9

docs/rules/always-return.md

@@ -78,11 +78,11 @@ promise
   })
 
 // NG
-var v = promise.then((x) => {
+const v = promise.then((x) => {
   console.log(x)
 })
 // NG
-var v = await promise.then((x) => {
+const v = await promise.then((x) => {
   console.log(x)
 })
 function foo() {

docs/rules/no-native.md

@@ -12,12 +12,12 @@ existence of a native promise implementation. Helpful if you want to use
 #### Valid
 
 ```js
-var Promise = require('bluebird')
-var x = Promise.resolve('good')
+const Promise = require('bluebird')
+const x = Promise.resolve('good')
 ```
 
 #### Invalid
 
 ```js
-var x = Promise.resolve('bad')
+const x = Promise.resolve('bad')
 ```