docs: remove knative refs (#10487)

# Which Problems Are Solved

Broken links to the removed Knative docs are removed.

# How the Problems Are Solved

I searched for case insensitive knative occurrences in the whole project
and handled them.

# Additional Context

[Reported
internallly](https://zitadel.slack.com/archives/C087ADF8LRX/p1755182839818719?thread_ts=1755170846.959129&cid=C087ADF8LRX)

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

@@ -8,7 +8,6 @@ Choose your platform and run ZITADEL with the most minimal configuration possibl
 - [Linux](./linux)
 - [MacOS](./macos)
 - [Docker Compose](./compose)
-- [Knative](./knative)
 - [Kubernetes](./kubernetes)
 
 ## Prerequisites

docs/docs/self-hosting/manage/updating_scaling.md

@@ -23,7 +23,7 @@ For production setups, we recommend that you [run ZITADEL in a highly available
 As all shared state is managed in the database,
 the ZITADEL binary itself is stateless.
 You can easily run as many ZITADEL binaries in parallel as you want.
-If you use [Knative](/docs/self-hosting/deploy/knative)
+If you use [Knative](https://knative.dev/docs/)
 or [Google Cloud Run](https://cloud.google.com/run) (which uses Knative, too),
 you can even scale to zero.
 Especially if you use an autoscaler that scales to zero,