add NEWS [ci skip]

NEWS.md

@@ -10,6 +10,9 @@ New language features
   and associativity as other arrow-like operators ([#36666]).
 * Compilation and type inference can now be enabled or disabled at the module level
   using the experimental macro `Base.Experimental.@compiler_options` ([#37041]).
+* The postfix conjugate transpose operator `'` now accepts Unicode modifiers as
+  suffixes, so e.g. `a'ᵀ` is parsed as `var"'ᵀ"(a)`, which can be defined by the
+  user. `a'ᵀ` parsed as `a' * ᵀ` before, so this is a minor change ([#37247]).
 
 Language changes
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