[clang-tidy][test] Add trailing -- to suppress compile_commands.json …

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This fixes some build bots if we reland D150505: specifically when using GCC to
build LLVM and then `-fno-lifetime-dse` ends up passed to compile_commands.json
and causing clang-tidy to pick up the Clang unknown option.

clang-tools-extra/test/clang-tidy/checkers/performance/trivially-destructible.cpp

@@ -1,7 +1,7 @@
 // RUN: %check_clang_tidy %s performance-trivially-destructible %t
 // RUN: grep -Ev "// *[A-Z-]+:" %s > %t.cpp
-// RUN: clang-tidy %t.cpp -checks='-*,performance-trivially-destructible' -fix
-// RUN: clang-tidy %t.cpp -checks='-*,performance-trivially-destructible' -warnings-as-errors='-*,performance-trivially-destructible'
+// RUN: clang-tidy %t.cpp -checks='-*,performance-trivially-destructible' -fix --
+// RUN: clang-tidy %t.cpp -checks='-*,performance-trivially-destructible' -warnings-as-errors='-*,performance-trivially-destructible' --
 
 struct TriviallyDestructible1 {
   int a;