[build] Roll isolate binaries

This ports:
https://chromium-review.googlesource.com/c/chromium/src/+/696886

Bug: chromium:692940, chromium:524758
Change-Id: I158d996ff76c354b8a672b085d476e9687205034
Reviewed-on: https://chromium-review.googlesource.com/700455Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48282}

tools/luci-go/linux64/isolate.sha1

-21410c557b49620e8a44ec0f861f94605bdc6d5c
+ccdea1387f9f26c2572bf5f2b8d24e8d66a69cf6

tools/luci-go/mac64/isolate.sha1

-1966687828a068eee4c5da45bbb8afd91cddda6f
+71329e82d274b847525f2b6345cb9fb6ddd0fff3

tools/luci-go/win64/isolate.exe.sha1

-35482264cea0f9b9dd2efe0a01620557fc15b7c1
+ded0dc9247e06fa42b653cce43f461f243ebea8b