Update regex reduce_uri utils

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#2936 (comment)

Author: MathiusD

src/invidious/helpers/utils.cr

@@ -367,7 +367,7 @@ def fetch_random_instance
 end
 
 def reduce_uri(uri : URI | String, max_length : Int32 = 50, suffix : String = "…") : String
-  str = uri.to_s.sub(/https?:\/\//, "")
+  str = uri.to_s.sub(/^https?:\/\//, "")
   if str.size > max_length
     str = "#{str[0, max_length]}#{suffix}"
   end