Fix typo: datas tore -> data store

Closes elastic#298

Author: bertvan

Diff for: 075_Inside_a_shard/10_Intro.asciidoc

@@ -15,7 +15,7 @@ In this chapter, we answer these questions:
 
 The easiest way to understand how a shard functions today is to start with a
 history lesson. We will look at the problems that needed to be solved in order
-to provide a distributed durable datas tore with near real-time search and
+to provide a distributed durable data store with near real-time search and
 analytics.
 
 .Content Warning