Remove unsupported OKX Explorer entry

[leonschh]

Summary

Atm, the OKX link leads to 404.

• Verified the current OKX Explorer and could not find Ink among the supported networks.
• Removed the outdated OKX Explorer entry from the documentation.

[kutluhaneth46]

Review

Same class of change as the Routescan PR: removes the OKX Explorer section cleanly.

Advisory ask for maintainers/author — please confirm OKX no longer indexes Ink (or is intentionally unlisted). If the explorer still works and only the marketing copy is stale, a link/copy refresh would preserve the option for users who prefer OKX’s multichain UX.

No code concerns with the deletion itself.

[leonschh]

Review

Same class of change as the Routescan PR: removes the OKX Explorer section cleanly.

Advisory ask for maintainers/author — please confirm OKX no longer indexes Ink (or is intentionally unlisted). If the explorer still works and only the marketing copy is stale, a link/copy refresh would preserve the option for users who prefer OKX’s multichain UX.

No code concerns with the deletion itself.

Just like in Routescan, the network isn't supported; as you can see in the screenshot below, a search for Ink on OKX returns no results.
I also manually checked all the networks and didn't find the Ink chain.

[kutluhaneth46]

Verified: OKX Ink explorer entry is gone/unsupported. LGTM removing the stale section.