remove extra linebreaks (#10184)

2 consecutive empty lines

Author: browner12

collections.md

@@ -442,7 +442,6 @@ $collection = collect([
     ['third'  => collect([7, 8, 9])]
 ]);
 
-
 $collapsed = $collection->collapseWithKeys();
 
 $collapsed->all();
@@ -3594,7 +3593,6 @@ $collection->all();
 
 // ['Michael', 'Tom']
 
-
 $collection = collect();
 
 $collection->whenEmpty(function (Collection $collection) {
@@ -3640,7 +3638,6 @@ $collection->all();
 
 // ['michael', 'tom', 'adam']
 
-
 $collection = collect();
 
 $collection->whenNotEmpty(function (Collection $collection) {

dusk.md

@@ -1958,7 +1958,6 @@ Assert that the element matching the given selector is missing the provided attr
 $browser->assertAttributeMissing($selector, $attribute);
 ```
 
-
 <a name="assert-attribute-contains"></a>
 #### assertAttributeContains