Update sandbox.adoc

documentation/sandbox.adoc

@@ -9,7 +9,7 @@ This principle is not very easy to archive on the same computer since you have t
 Different projects on the same computer...
 
 * ... may want to use the same tool (`java`, `mvn`, `node`, `python`, you name it).
-* ... want define their on version for tool `xyz` to be used that may be the same or differ between the projects.
+* ... want to define their own version for tool `xyz` to be used that may be the same or differ between the projects.
 * ... want to have their individual configuration for a tool (e.g. assuming your are using `AWS CLI` in two projects on the same computer but for two different tenants. You do not want to accidentally deploy something for the wrong account because you share a global configuration for your login, do you?)
 * ... may want to use the same tool (e.g. an IDE like `Intellij`, `Eclipse`, `VSCode`, etc.) but with different plugins.