[12.x] Add Str::uuid7 to string helpers (#10213)

* Add uuid7 string helper

* Update strings.md

---------

Co-authored-by: Taylor Otwell <[email protected]>

Author: christophstockinger

strings.md

@@ -110,6 +110,7 @@ Laravel includes a variety of functions for manipulating string values. Many of
 [Str::ulid](#method-str-ulid)
 [Str::unwrap](#method-str-unwrap)
 [Str::uuid](#method-str-uuid)
+[Str::uuid7](#method-str-uuid7)
 [Str::wordCount](#method-str-word-count)
 [Str::wordWrap](#method-str-word-wrap)
 [Str::words](#method-str-words)
@@ -1682,6 +1683,23 @@ To instruct the `uuid` method to return to generating UUIDs normally, you may in
 Str::createUuidsNormally();
 ```
 
+<a name="method-str-uuid7"></a>
+#### `Str::uuid7()` {.collection-method}
+
+The `Str::uuid7` method generates a UUID (version 7):
+
+```php
+use Illuminate\Support\Str;
+
+return (string) Str::uuid7();
+```
+
+A `DateTimeInterface` may be passed as an optional parameter which will be used to generate the ordered UUID:
+
+```php
+return (string) Str::uuid7(time: now());
+```
+
 <a name="method-str-word-count"></a>
 #### `Str::wordCount()` {.collection-method}