[compile] update the braft vesion

[cw123]

Describe the feature you'd like:

curve uses braft as the consensus protocol, the braft version we are currently using is too old. Hope to be able to upgrade braft to a newer version.

The external dependencies used by curve are documented in https://github.com/opencurve/curve/blob/master/WORKSPACE. The currently used version of braft is:

curve使用braft作为一致性协议，我们当前使用的braft版本太老了。希望能够把braft的升级到一个比较新的稳定版本。

curve使用的外部依赖库记录在 https://github.com/opencurve/curve/blob/master/WORKSPACE 这个文件中。其中braft的当前使用的版本为：

git_repository(
    name = "com_github_baidu_braft",
    remote = "https://github.com/baidu/braft",
    commit = "e255c0e4b18d1a8a5d484d4b647f41ff1385ef1e",
)

Replace the old commit with the new version of the commit, and then make build compiles the entire curve project, some compilation errors may occur. You need to find a way to solve these compilation problems and complete the version replacement of braft.

使用新版本的commit替换这个旧的commit，然后make build编译整个curve工程，可能会出现一些编译错误。你需要想办法解决这些编译问题，完成braft的版本替换。

Teachability, Documentation, Adoption, Migration Strategy:

Build compilation environment：https://github.com/opencurve/curve/blob/master/docs/cn/build_and_run.md.

[tangwz]

/assign