docs: grammar in start_link_supervised/2 (#12858)

Author: mhanberg

lib/ex_unit/lib/ex_unit/callbacks.ex

@@ -593,7 +593,7 @@ defmodule ExUnit.Callbacks do
   If the process that was started crashes, the crash is propagated to the test process,
   failing the test and printing the cause of the crash.
 
-  Note that if the started terminates before it is linked to the test process,
+  Note that if the started process terminates before it is linked to the test process,
   this function will exit with reason `:noproc`.
   """
   @doc since: "1.14.0"