fix syntax highlight in Readme

README.md

@@ -4,7 +4,7 @@ Lightweight implementation of [GitLab CE API](https://docs.gitlab.com/ce/api/) i
 
 ## Quick start
 
-```{.pl}
+```perl
 use GitLab;
 
 my $gitlab = GitLab::API->new(
@@ -41,4 +41,4 @@ my $groups = $gitlab->groups(search => "pb161");
 
 ## Author
 
-Roman Lacko <[`xlacko1@fi.muni.cz`](mailto:xlacko1@fi.muni.cz)>
\ No newline at end of file
+Roman Lacko <[`xlacko1@fi.muni.cz`](mailto:xlacko1@fi.muni.cz)>