Sync docs from Discourse (#407)

Sync charm docs from https://discourse.charmhub.io

Co-authored-by: GitHub Actions <41898282+github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

docs/reference/r-releases.md

@@ -3,6 +3,7 @@
 The release notes for stable releases can be found in the charm's [GitHub releases page](https://github.com/canonical/mysql-router-k8s-operator/releases).
 
 The following revisions have been published in the `8.0/stable` [channel](https://juju.is/docs/sdk/channel):
+* [Revisions 598, 599](https://github.com/canonical/mysql-router-k8s-operator/releases/tag/rev598)
 * [Revisions 530, 531](https://github.com/canonical/mysql-router-k8s-operator/releases/tag/rev530)
 * [Revisions 154, 155](https://github.com/canonical/mysql-router-k8s-operator/releases/tag/rev154)
 * [Revision 117](https://github.com/canonical/mysql-router-k8s-operator/releases/tag/rev117)

docs/reference/r-system-requirements.md

@@ -23,7 +23,7 @@ Make sure your machine meets the following requirements:
 
 ## Supported architectures
 
-The charm is based on [ROCK OCI](https://github.com/canonical/charmed-mysql-rock) named "[charmed-mysql](https://github.com/canonical/charmed-mysql-rock/pkgs/container/charmed-mysql)", which is recursively based on SNAP "[charmed-mysql](https://snapcraft.io/charmed-mysql)", which is currently available for `amd64` only! The architecture `arm64` support is planned. Please [contact us](/t/12177) if you are interested in new architecture!
+The charm is based on [ROCK OCI](https://github.com/canonical/charmed-mysql-rock) named "[charmed-mysql](https://github.com/canonical/charmed-mysql-rock/pkgs/container/charmed-mysql)", which is recursively based on SNAP "[charmed-mysql](https://snapcraft.io/charmed-mysql)", which is currently available for `amd64` and `arm64` only! Please [contact us](/t/12177) if you are interested in new architecture!
 
 <a name="mysql-gr-limits"></a>
 ## Charmed MySQL K8s requirements