docs(readme): update latest stable version tag (#3179)

README.md

@@ -85,23 +85,23 @@ Using [vim-plug](https://github.com/junegunn/vim-plug)
 
 ```viml
 Plug 'nvim-lua/plenary.nvim'
-Plug 'nvim-telescope/telescope.nvim', { 'tag': '0.1.6' }
+Plug 'nvim-telescope/telescope.nvim', { 'tag': '0.1.8' }
 " or                                , { 'branch': '0.1.x' }
 ```
 
 Using [dein](https://github.com/Shougo/dein.vim)
 
 ```viml
 call dein#add('nvim-lua/plenary.nvim')
-call dein#add('nvim-telescope/telescope.nvim', { 'rev': '0.1.6' })
+call dein#add('nvim-telescope/telescope.nvim', { 'rev': '0.1.8' })
 " or                                         , { 'rev': '0.1.x' })
 ```
 
 Using [packer.nvim](https://github.com/wbthomason/packer.nvim)
 
 ```lua
 use {
-  'nvim-telescope/telescope.nvim', tag = '0.1.6',
+  'nvim-telescope/telescope.nvim', tag = '0.1.8',
 -- or                            , branch = '0.1.x',
   requires = { {'nvim-lua/plenary.nvim'} }
 }
@@ -112,14 +112,14 @@ Using [lazy.nvim](https://github.com/folke/lazy.nvim)
 ```lua
 -- init.lua:
     {
-    'nvim-telescope/telescope.nvim', tag = '0.1.6',
+    'nvim-telescope/telescope.nvim', tag = '0.1.8',
 -- or                              , branch = '0.1.x',
       dependencies = { 'nvim-lua/plenary.nvim' }
     }
 
 -- plugins/telescope.lua:
 return {
-    'nvim-telescope/telescope.nvim', tag = '0.1.6',
+    'nvim-telescope/telescope.nvim', tag = '0.1.8',
 -- or                              , branch = '0.1.x',
       dependencies = { 'nvim-lua/plenary.nvim' }
     }