Spring ReactorServerHttpRequest does not reflect forwarded host and port when forwarding-header-strategy=native or cloud platform detected

Backport of gh-28601

Comment From: rstoyanchev

Closed with a2b7a907ec8aa5f34a20f533a064067e56ef6967.

Comment From: rstoyanchev

Re-opening due to follow-up reports, see #30033 and linked issue, and since this is not yet released.

Comment From: rstoyanchev

Part of the fixes are on the Reactor Netty side, https://github.com/reactor/reactor-netty/issues/2711 and https://github.com/reactor/reactor-netty/pull/2714. For those we need reactor-bom 2020.0.29, but we should have 2020.0.30 to upgrade to in #30116.