[ci skip] Add the 'random' extension to labeler.yml (#9050)

see 4d8dd8d

Author: TimWolla

.github/labeler.yml

@@ -146,6 +146,9 @@
 "Extension: pspell":
 - ext/pspell/**/*
 
+"Extension: random":
+- ext/random/**/*
+
 "Extension: readline":
 - ext/readline/**/*