SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
This is the JSTestRunnerCounts struct from test-js and test-web (but
using unsigned integers - no negative counts). Not all test runners will
use all fields, but all will want to keep track of various counts.
The test-js reporter is arguably the nicest test runner / reporter that
exists in the serenity code base. To the goal of leveling up all the
other unit test environments, start a new LibTest library so that we
can share code and reporting utilities to make all the test systems
look and behave similarly.
