DOC-4749 DOC-2446 Created release notes draft for the RS 7.8.4 maintenance release that includes Ubuntu 22 support

Author: rrelledge

content/operate/rs/release-notes/rs-7-8-releases/_index.md

@@ -209,6 +209,7 @@ The following table provides a snapshot of supported platforms as of this Redis
 | RHEL 9<br />FIPS mode<sup>[5](#table-note-5)</sup> | <span title="Supported">&#x2705;</span> | – | – | – | – |
 | RHEL 8 &<br />compatible distros<sup>[1](#table-note-1)</sup> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> |
 | RHEL 7 &<br />compatible distros<sup>[1](#table-note-1)</sup> | – | – | <span title="Deprecated" class="font-serif">:warning:</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> |
+| Ubuntu 22.04<sup>[2](#table-note-2)</sup> | <span title="Supported">&#x2705;</span> | – | – | – | – |
 | Ubuntu 20.04<sup>[2](#table-note-2)</sup> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> | – |
 | Ubuntu 18.04<sup>[2](#table-note-2)</sup> | – | <span title="Deprecated" class="font-serif">:warning:</span> | <span title="Deprecated" class="font-serif">:warning:</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> |
 | Ubuntu 16.04<sup>[2](#table-note-2)</sup> | – | – | <span title="Deprecated" class="font-serif">:warning:</span> | <span title="Supported">&#x2705;</span> | <span title="Supported">&#x2705;</span> |