[common, fs] include missing header introduced on #330 (#370)

Signed-off-by: Caio Oliveira <caiooliveirafarias0@gmail.com>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/370
Reviewed-by: crueter <crueter@eden-emu.dev>
Reviewed-by: Lizzie <lizzie@eden-emu.dev>
Co-authored-by: Caio Oliveira <caiooliveirafarias0@gmail.com>
Co-committed-by: Caio Oliveira <caiooliveirafarias0@gmail.com>

src/common/string_util.h

@@ -7,6 +7,7 @@
 
 #pragma once
 
+#include <algorithm>
 #include <cstddef>
 #include <span>
 #include <string>