@Nullable
    default Integer defaultMaxClientHelloLength() {
        return null;
    }
Returns the default maximum client hello length that a server allows.
The length shouldn't exceed 16MiB as described in
<a href="https://datatracker.ietf.org/doc/html/rfc5246#section-7.4">Handshake Protocol</a>.

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