Inconsistency between code snippet and explanation in ASM-1

[BinderDavid]

A previous commit changed the code snippet to also include a newline after "hello, world!". The following line is therefore no longer in sync with the code.

asm/content/asm_1.md

Line 244 in 0b63ccb

The next step is to prepare the second argument of the `sys_write` system call. In our case, we pass the address of the `msg` variable to the `rsi` register. Last but not least, we should specify the length of data we want to write. The length of the `hello, world!` string is `13` bytes, so we pass it to the `rdx` register.

[0xAX]

ah, good catch @BinderDavid, thank you, I will fix