@Nullable
    default Long defaultHttp2MaxStreamsPerConnection() {
        return null;
    }
Returns the default value of the {@link ServerBuilder#http2MaxStreamsPerConnection(long)} option.
Note that this flag has no effect if a user specified the value explicitly via
{@link ServerBuilder#http2MaxStreamsPerConnection(long)}.

<p>The default value of this flag is
{@value DefaultFlagsProvider#DEFAULT_HTTP2_MAX_STREAMS_PER_CONNECTION}.
Specify the {@code -Dcom.linecorp.armeria.defaultHttp2MaxStreamsPerConnection=<integer>} JVM option
to override the default value.
core/src/main/java/com/linecorp/armeria/common/FlagsProvider.java