update icon & readme

Author: PssbleTrngle

README.md

@@ -7,7 +7,7 @@
 [CURSEFORGE]: https://www.curseforge.com/minecraft/mc-mods/create-jetpack
 [MODRINTH]: https://modrinth.com/mod/create-jetpack
 
-# Create Jetpack <!-- modrinth_exclude.start --> <img src="https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.19.x/src/main/resources/assets/create_jetpack/icon.png" align="right" height="128" />
+# Create Jetpack <!-- modrinth_exclude.start --> <img src="https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.21.x/src/main/resources/assets/create_jetpack/icon.png" align="right" height="128" />
 
 [Looking for the Fabric version?](https://github.com/PssbleTrngle/CreateJetpack-Fabric)
 
@@ -36,18 +36,18 @@ Like the copper backtank, the jetpack does also go in the chest slot,
 feeds air to items like the extendo-grip and can be enchanted with _Capacity_.
 Just like the backtank it is charged by placing it down and supplying it with rotational force.
 
-![Usage](https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.19.x/screenshots/usage.png)
+![Usage](https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.21.x/screenshots/usage.png)
 
 When underwater while sprint-swimming, the jetpack boosts your swimming speed.
 Additionally, the hover-mode prevents you from floating downwards.
 
-![Underwater Usage](https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.19.x/screenshots/underwater.png)
+![Underwater Usage](https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.21.x/screenshots/underwater.png)
 
 If a mod similar to [Elytra Slot](https://github.com/illusivesoulworks/elytraslot), 
 which enables equipping an elytra in addition to a chestplate, 
 the jetpack will instead give you firework-like boost while the player is pressing the `UP`-key.
 
-![Elytra Support](https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.19.x/screenshots/elytra.png)
+![Elytra Support](https://raw.githubusercontent.com/PssbleTrngle/CreateJetpack/1.21.x/screenshots/elytra.png)
 
 Curios Support is possible by adding it via a datapack. Save to following to `data/curios/tags/items/back.json`: