filter method
Returns a new suite with all tests matching test removed.
Unlike GroupEntry.filter, this never returns null. If all entries are
filtered out, it returns an empty suite.
Implementation
Suite filter(bool Function(Test) callback) {
var filtered = group.filter(callback);
filtered ??= Group.root([], metadata: metadata);
return Suite(
filtered,
platform,
ignoreTimeouts: ignoreTimeouts,
path: path,
);
}