[clang] [clang-tools-extra] [flang] [lld] [llvm] [LLVM][utils] Add script which clears release notes (PR #153593)

[Younan Zhang via cfe-commits]

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@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+
+# This script clears release notes, which is needed when bumping trunk version.
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zyn0217 wrote:

We may want a copyright header

https://github.com/llvm/llvm-project/pull/153593