docs: remove outdated comments from main.rb

lab3_task1_funcation_block_arg/main.rb

@@ -1,7 +1,4 @@
 
-# sort by and sort разница
-# enumurable isn't Module, it's Mixture. What is this?
-
 def indices_sorted_by_descending_values(array)
     array.each_with_index.to_a
       .sort_by { |(element, index)| -element }