[clang] [clang-format][NFC] Clean up FormatTokenLexer (PR #203825)

[Björn Schäpers via cfe-commits]

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@@ -1466,9 +1472,9 @@ FormatToken *FormatTokenLexer::getNextToken() {
         FormatTok->Tok.setKind(tok::kw_if);
       }
     } else if (FormatTok->is(tok::identifier)) {
-      if (MacroBlockBeginRegex.match(Text))
+      if (llvm::Regex(Style.MacroBlockBegin).match(Text))
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HazardyKnusperkeks wrote:

I don't think we should recreate the same regex over and over again.

https://github.com/llvm/llvm-project/pull/203825