[ssci] Add Shipped field to READMEs

This CL adds the Shipped field and updates the
License File field in Chromium READMEs within the
directory /third_party/jsoncpp.

See the LSC doc at go/lsc-chrome-metadata.

This CL was uploaded by git cl split.

R=jophba@chromium.org

Bug: b:285450740
Change-Id: I8bb226ee698668e38794712c2d7c99a4fbf9da57
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4663811
Reviewed-by: Jordan Bayles <jophba@chromium.org>
Commit-Queue: Anne Redulla <aredulla@google.com>
Cr-Commit-Position: refs/heads/main@{#1170186}
NOKEYCHECK=True
GitOrigin-RevId: aa8c182ea7fa29c7f05629b82d93541d3940a65c