Iron Jetpacks

Release 4.2.1 for MC 1.16.5

Changes:

- Added the ability to set a jetpacks 'armor toughness' and ';knockback resistance' values

- Added ru_ru translations

- Updated the 'vertical sprint modifier' values for the default jetpacks (requires the 'jetpacks' folder to be deleted to regenerate with the new values)

- Jetpack jsons now auto-update with new fields if they are added (doesn't change anything from a gameplay perspective)

- Made the jetpack and crafting component textures a bit lighter

- Moved default recipe configs to the common config

- Fixed holding 'sprint' and 'fly' keys while falling causing the player to fall faster

- Fixed item names not being translated properly in some cases