Merge pull request #1004 from KnudH/patch-1

update some links so point to v6 docs

Author: freekmurze

docs/introduction.md

@@ -23,7 +23,7 @@ $users = QueryBuilder::for(User::class)
 // all `User`s that contain the string "John" in their name
 ```
 
-[Read more about filtering features like: partial filters, exact filters, scope filters, custom filters, ignored values, default filter values, ...](https://spatie.be/docs/laravel-query-builder/v5/features/filtering/)
+[Read more about filtering features like: partial filters, exact filters, scope filters, custom filters, ignored values, default filter values, ...](https://spatie.be/docs/laravel-query-builder/v6/features/filtering/)
 
 ### Including relations based on a request: `/users?include=posts`:
 
@@ -35,7 +35,7 @@ $users = QueryBuilder::for(User::class)
 // all `User`s with their `posts` loaded
 ```
 
-[Read more about include features like: including nested relationships, including relationship count, ...](https://spatie.be/docs/laravel-query-builder/v5/features/including-relationships/)
+[Read more about include features like: including nested relationships, including relationship count, ...](https://spatie.be/docs/laravel-query-builder/v6/features/including-relationships/)
 
 ### Sorting a query based on a request: `/users?sort=id`:
 
@@ -47,7 +47,7 @@ $users = QueryBuilder::for(User::class)
 // all `User`s sorted by ascending id
 ```
 
-[Read more about sorting features like: custom sorts, sort direction, ...](https://spatie.be/docs/laravel-query-builder/v5/features/sorting/)
+[Read more about sorting features like: custom sorts, sort direction, ...](https://spatie.be/docs/laravel-query-builder/v6/features/sorting/)
 
 ### Works together nicely with existing queries:
 
@@ -70,7 +70,7 @@ $users = QueryBuilder::for(User::class)
 // the fetched `User`s will only have their id & email set
 ```
 
-[Read more about selecting fields.](https://spatie.be/docs/laravel-query-builder/v5/features/selecting-fields/)
+[Read more about selecting fields.](https://spatie.be/docs/laravel-query-builder/v6/features/selecting-fields/)
 
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