Update README.md

Author: GrahamCampbell

README.md

@@ -38,13 +38,13 @@ $ composer require m4tthumphrey/php-gitlab-api:^9.19 php-http/guzzle6-adapter:^2
 #### Laravel 5.5+:
 
 ```
-$ composer require graham-campbell/gitlab:^2.8 php-http/guzzle6-adapter:^2.0.1
+$ composer require graham-campbell/gitlab:^2.7 php-http/guzzle6-adapter:^2.0.1
 ```
 
 #### Laravel 6+:
 
 ```
-$ composer require graham-campbell/gitlab:^3.3 php-http/guzzle6-adapter:^2.0.1
+$ composer require graham-campbell/gitlab:^3.2 php-http/guzzle6-adapter:^2.0.1
 ```
 
 #### Symfony 2.6+: