Quieter fxtest logger

[satazor]

Is your feature request related to a problem? Please describe.

The current fxtest logger provided by fxtest.WithTestLogger is quite verbose, printing everything. When something fails in tests, I have to scroll down all the log messages until I find information about the actual error.

Describe the solution you'd like
An option that would print only errors, akin to how fxevent.SlogLogger where we can do:

	slogger := &fxevent.SlogLogger{Logger: slog.Default()}
	slogger.UseLogLevel(-1000)

To suppress every log, except errors.

Describe alternatives you've considered
Implementing a package like so:

// tbWriter is a io.Writer that writes to the provided test logger.
type tbWriter struct {
	t testing.TB
}

// Write writes the provided bytes to the underlying testing.TB.
func (w tbWriter) Write(bs []byte) (int, error) {
	w.t.Logf("%s", bs)

	return len(bs), nil
}

// QuietConsoleLogger is a fx logger that only logs errors.
type QuietConsoleLogger struct {
	fxevent.ConsoleLogger
}

// LogEvent logs the provided event if it is an error.
func (m QuietConsoleLogger) LogEvent(event fxevent.Event) {
	rv := reflect.Indirect(reflect.ValueOf(event))
	errRv := rv.FieldByName("Err")

	if !errRv.IsValid() {
		return
	}

	err, ok := errRv.Interface().(error)

	if ok && err != nil {
		m.ConsoleLogger.LogEvent(event)
	}
}

// WithQuietTestLogger provides a fx logger for tests that is silent except on errors.
func WithQuietTestLogger(t testing.TB) fxevent.Logger {
	return QuietConsoleLogger{
		ConsoleLogger: fxevent.ConsoleLogger{
			W: tbWriter{t},
		},
	}
}

Is this a breaking change?
No.

Additional context
N/A