Fix instructions in docs

Author: zeyi2

clang-tools-extra/docs/clang-tidy/checks/modernize/avoid-setjmp-longjmp.rst

@@ -5,6 +5,8 @@ modernize-avoid-setjmp-longjmp
 
 Flags all call expressions involving ``setjmp()`` and ``longjmp()`` in C++ code.
 
+Exception handling with ``throw`` and ``catch`` should be used instead.
+
 References
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