NO-ISSUE fix markdown format

Author: Yang-33

examples/v1/echobot/README.md

@@ -4,7 +4,7 @@ An example LINE bot just to echo messages
 
 ## Getting started
 
-```ruby
+```sh
 $ export LINE_CHANNEL_SECRET=YOUR_CHANNEL_SECRET
 $ export LINE_CHANNEL_ACCESS_TOKEN=YOUR_CHANNEL_ACCESS_TOKEN
 $ bundle install

examples/v1/kitchensink/README.md

@@ -4,7 +4,7 @@ A kitchen-sink LINE bot example
 
 ## Getting started
 
-```ruby
+```sh
 $ export LINE_CHANNEL_SECRET=YOUR_CHANNEL_SECRET
 $ export LINE_CHANNEL_ACCESS_TOKEN=YOUR_CHANNEL_ACCESS_TOKEN
 $ bundle install

examples/v1/rich_menu/README.md

@@ -4,7 +4,7 @@
 
 ## Getting started
 
-```ruby
+```sh
 $ export LINE_CHANNEL_SECRET=YOUR_CHANNEL_SECRET
 $ export LINE_CHANNEL_ACCESS_TOKEN=YOUR_CHANNEL_ACCESS_TOKEN
 $ bundle install

examples/v2/audience/README.md

@@ -5,7 +5,7 @@
 ## Getting started
 Update User ID of `app.rb` and `audience.txt' to your own.
 
-```ruby
+```sh
 $ export LINE_CHANNEL_SECRET=YOUR_CHANNEL_SECRET
 $ export LINE_CHANNEL_ACCESS_TOKEN=YOUR_CHANNEL_ACCESS_TOKEN
 $ bundle install

examples/v2/channel_access_token/README.md

@@ -4,7 +4,7 @@
 
 ## Getting started
 
-```ruby
+```sh
 $ export LINE_CHANNEL_ID=YOUR_CHANNEL_ID
 $ export LINE_CHANNEL_SECRET=YOUR_CHANNEL_SECRET
 $ bundle install

examples/v2/rich_menu/README.md

@@ -4,7 +4,7 @@
 
 ## Getting started
 
-```ruby
+```sh
 $ export LINE_CHANNEL_SECRET=YOUR_CHANNEL_SECRET
 $ export LINE_CHANNEL_ACCESS_TOKEN=YOUR_CHANNEL_ACCESS_TOKEN
 $ bundle install