List version 0.9.0, and handle rgbasm-old.5 in docusaurus

Author: Rangi42

docusaurus.config.js

@@ -81,6 +81,7 @@ const config = {
           "gbz80.7",
           "rgbasm.1",
           "rgbasm.5",
+          "rgbasm-old.5",
           "rgbds.5",
           "rgbds.7",
           "rgbfix.1",

src/pages/versions.mdx

@@ -8,6 +8,7 @@ If you have an older project that no longer compiles using the latest RGBDS, and
 
 | Version | Release date | Object version | Notes |
 | --- | --- | --- | --- |
+| [0.9.0](https://github.com/gbdev/rgbds/releases/tag/v0.9.0) | 2024-12-25 | [v9 r11](https://rgbds.gbdev.io/docs/v0.9.0/rgbds.5) | |
 | [0.9.0-rc2](https://github.com/gbdev/rgbds/releases/tag/v0.9.0-rc2) | 2024-10-21 | v9 r11 | |
 | [0.9.0-rc1](https://github.com/gbdev/rgbds/releases/tag/v0.9.0-rc1) | 2024-09-18 | v9 r11 | |
 | [0.8.0](https://github.com/gbdev/rgbds/releases/tag/v0.8.0) | 2024-06-28 | [v9 r10](https://rgbds.gbdev.io/docs/v0.8.0/rgbds.5) | |