[clang-tools-extra] [clang-doc] Add HTMLMustacheGenerator.cpp (PR #138060)

[Daniel Thornburgh via cfe-commits]

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@@ -0,0 +1,85 @@
+//===-- HTMLMustacheGenerator.cpp - HTML Mustache Generator -----*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
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mysterymath wrote:

nit: Blank line between file header and first `#include`

https://github.com/llvm/llvm-project/pull/138060