use css truncate everywhere and remove StringUtils.truncate function (#513)

Co-authored-by: robs <git@robs.social>

lib/pinchflat/utils/string_utils.ex

@@ -25,23 +25,6 @@ defmodule Pinchflat.Utils.StringUtils do
     |> String.slice(0..(length - 1))
   end
 
-  @doc """
-  Truncates a string to the given length and adds `...` if the string is longer than the given length.
-  Will break on a word boundary. Nothing happens if the string is shorter than the given length.
-
-  Returns binary()
-  """
-  def truncate(string, length) do
-    if String.length(string) > length do
-      string
-      |> String.slice(0..(length - 1))
-      |> String.replace(~r/\s+\S*$/, "")
-      |> Kernel.<>("...")
-    else
-      string
-    end
-  end
-
   @doc """
   Wraps a string in double braces. Useful as a UI helper now that
   LiveView 1.0.0 allows `{}` for interpolation so now we can't use braces