Replaces every / and \ in path with separator (the platform's by default), in place. path must
be writable, not a string literal.
path_overwrite_separators :: (path: string, separator: u8 = PATH_SEPARATOR)
Parameters
- path: string
- separator: u8
path := copy_string("a/b\\c");
defer free(path);
path_overwrite_separators(path, #char "/");
assert(path == "a/b/c");