Use released clang-format instead of the one from dev branch (#9646)

Summary:
We should use the released clang-format version instead of the one from
dev branch. Otherwise the format report could be inconsistent with local
development env and CI. e.g.: https://github.com/facebook/rocksdb/issues/9644

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9646

Test Plan: CI

Reviewed By: riversand963

Differential Revision: D34554065

Pulled By: jay-zhuang

fbshipit-source-id: b841bc400becb4272be18c803eb03a7a1172da6f

.github/workflows/sanity_check.yml

@@ -32,7 +32,7 @@ jobs:
     - name: Download clang-format-diff.py
       uses: wei/wget@v1
       with:
-        args: https://raw.githubusercontent.com/llvm/llvm-project/main/clang/tools/clang-format/clang-format-diff.py
+        args: https://raw.githubusercontent.com/llvm/llvm-project/release/12.x/clang/tools/clang-format/clang-format-diff.py
 
     - name: Check format
       run: VERBOSE_CHECK=1 make check-format