[clang-tools-extra] [clang-tidy] Teach `readability-uppercase-literal-suffix` about C++23 and C23 suffixes (PR #148275)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,162 @@
+// TODO: When Clang adds support for decimal floating point types, enable these tests by:
+//    1. Removing all the #if 0 + #endif guards.
+//    2. Removing all occurrences of the string "DISABLED-" in this file.
+//    3. Deleting this message.
+
+// RUN: %check_clang_tidy -std=c23-or-later %s readability-uppercase-literal-suffix %t
+// RUN: grep -Ev "// *[A-Z-]+:" %s > %t.c
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vbvictor wrote:

Why do we need `grep`? What if build env doesn't have it, e.g. Windows

https://github.com/llvm/llvm-project/pull/148275