[clang] [analyzer][NFC] Fix typo in `exploredAllPaths` variable & predicate (PR #220588)

[Marco Milanese via cfe-commits]

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@@ -84,7 +84,7 @@ class CoreEngine {
 
   /// Whether the single-TU phase ran out of budget with work left over.
   /// The CTU phase replaces \c WList, so this has to be remembered separately.
-  bool exploredAllSTUPaths = false;
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marco-milanese-sonarsource wrote:

[265da4b](https://github.com/llvm/llvm-project/pull/220588/commits/265da4bf869cf3c4ac477b69a765f7447a9060e0)

https://github.com/llvm/llvm-project/pull/220588