fix the script to format code

[qiwzhang]

Signed-off-by: Wayne Zhang qiwzhang@google.com

Notes:

• Original "http" doesn't work any more. need to use "https"
• Keep using the old 3.8.0. The latest clang-format versions pre-build binaries are in github, requires some redirection or permission, did not figure out how to download them in curl.

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