build: silencing absl logspam (#21048)
build: silencing absl logspam (#21048)

The absl flagsaver logs every time it restores flags and this is the best way I can find to silence it
https://github.com/abseil/abseil-cpp/blob/master/absl/base/internal/raw_logging.cc#L147

Signed-off-by: Alyssa Wilk <b9253d1ec9cc3e9d2aab68d288ba3dab3452adf6@chromium.org>
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