discovery: update LICENSE formatting
discovery: update LICENSE formatting

The LICENSE file formatting is updated to match the standard Go BSD
license.

Change-Id: I507d7d13e01873cfac6ab8f359de4f56409b4497
Reviewed-on: https://team-review.git.corp.google.com/c/417742
Reviewed-by: Andrew Bonventre <682ad9f487f614f19e8b7cc5d340bdc8e1c1b128@google.com>

golang/pkgsite,golang/pkgsite,golang/pkgsite,golang/pkgsite