public long currentTimeMs() {
        return currentTimeMs;
    }
Get the current time in milliseconds. This will return the same cached value until the timer
has been updated using one of the {@link #update()} methods or {@link #sleep(long)} is used.
<p>
Note that the value returned is guaranteed to increase monotonically even if the underlying
{@link Time} implementation goes backwards. Effectively, the timer will just wait for the
time to catch up.

@return The current cached time in milliseconds
s3stream/src/main/java/com/automq/stream/utils/Timer.java