error parsing regexp: invalid UTF-8: �\^�v�

[fitrarhm]

I got issue when using known plaintext that doesn't have valid UTF, whether it's in string mode or hex mode.

panic: regexp: Compile("\xe0\^\xc8v\xe0"): error parsing regexp: invalid UTF-8: �\^�v�

goroutine 1 [running]:
regexp.MustCompile({0xc00000e17a, 0x6})
C:/Program Files/Go/src/regexp/regexp.go:319 +0xbb
github.com/tomchop/unxor/unxorlib.FindKey({0xc00010a000, 0x80, 0x200}, {0xc00007dea0, 0x6, 0x20})
D:/GO/Developments/pkg/mod/github.com/tomchop/[email protected]/unxorlib/unxor.go:51 +0x3da
main.main()
D:/sample/test/unxor/unxor.go:53 +0x265