Update sklmessages_en_US.properties

[AquaCobalt]

Fixed 2 typos - In line 61 and 62. On line 61 - changed "crash.vanilla=Using magic and love, we've managed to gather some details about the crash, and we will investigate this as soon as we can. You can see the full report below." Changed "we've" to "we've". On line 63 - changed "crash.modded=We think your game may be modded, and as such we can't accept this crash report. However, if you do indeed use mods, please send this to the mod authors to take a look at. crash.open=Open report file crash.alert.title=Oops! The game has crashed". Changed "can't" to "can't".

That's it!