Docs: correct spelling inconsistency

[davidmerkt]

In the documentation pages, there is inconsistency in the spelling of the suggested wording of the firewall rules. Some of the firewall rules use the British English spelling of the word "standardised" but on the very same page, 2 lines down, another rule uses the American English spelling "standardized". This inconsistency does not match the professionalism that the project would like to present.

As an example, in the English language documentation (/docs/en/node-staking/securing-your-node.mdx):

Allow execution client (formerly referred to as ETH1):
sudo ufw allow 30303/tcp comment 'Execution client port, **standardized** by Rocket Pool'
sudo ufw allow 30303/udp comment 'Execution client port, **standardized** by Rocket Pool'

Allow consensus client (formerly referred to as ETH2):
sudo ufw allow 9001/tcp comment 'Consensus client port, **standardized** by Rocket Pool'
sudo ufw allow 9001/udp comment 'Consensus client port, **standardized** by Rocket Pool'

If you run lighthouse client v4.5.0+, you can use quic protocol to reduce latency / increase bandwidth, quic protocol uses lighthouse's --port + 1 to listen for quic messages by default: https://lighthouse-blog.sigmaprime.io/Quic,%20Networking.html

sudo ufw allow 8001/udp comment 'Consensus client port, **standardised** by Rocket Pool'