docs: Warn users of Zitadel 4 install incompatibility with Linux (#10620)

# Which Problems Are Solved

Gives users a heads up before they start installing Zitadel's latest
version, Zitadel 4

- Instruction for Zitadel 4 do not exist and the Linux guide is
misleading

# How the Problems Are Solved

For example:
- Warns users that the Linux version is not ready for Zitadel 4 and that
they should use the Docker version instead

# Additional Context

- Discussion #10526

Co-authored-by: Ramon <mail@conblem.me>
Co-authored-by: Marco A. <marco@zitadel.com>

docs/docs/self-hosting/deploy/linux.mdx

@@ -8,6 +8,14 @@ import DefaultUser from "./_defaultuser.mdx";
 import Next from "./_next.mdx";
 import NoteInstanceNotFound from "./troubleshooting/_note_instance_not_found.mdx";
 
+:::caution
+
+Be aware! This guide does not work for the newly updated version of Zitadel 4! [Learn more](https://github.com/zitadel/zitadel/issues/10526)
+
+Please use Docker version if you want to use Zitadel 4.
+
+:::
+
 ## Install PostgreSQL
 
 Download a `postgresql` binary as described [in the PostgreSQL docs](https://www.postgresql.org/download/linux/).