Merge #21604: test: Document why no symbol names can be used for suppressions

fa04eb7d78 test: Document why no symbol names can be used for suppressions (MarcoFalke)

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Tree-SHA512: 02e5d9cb3ca299b5e7f1f0f780af514692147f5f0846e21e5375a99e90d3aed3a3489c674ac0eb90ae34d60f576410ba1d926d5ca70cdce4f9c7a111cd516adf

test/sanitizer_suppressions/ubsan

@@ -1,6 +1,10 @@
 # -fsanitize=undefined suppressions
 # =================================
-signed-integer-overflow:CTxMemPool::PrioritiseTransaction
+# This would be `signed-integer-overflow:CTxMemPool::PrioritiseTransaction`,
+# however due to a bug in clang the symbolizer is disabled and thus no symbol
+# names can be used.
+# See https://github.com/google/sanitizers/issues/1364
+signed-integer-overflow:txmempool.cpp
 
 # -fsanitize=integer suppressions
 # ===============================