feat: use mbstring if iconv is not working

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

feat: use mbstring if iconv is not working

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

chore: update CI

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

chore: add php82 benchmark

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

refactor: probably fix some issues?

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

fix: workaround alpine iconv doesn't have UTF-32 header

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

chore(ci): add test against PHP 8.1

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

chore: update deps

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

Release of new version 1.4.2

Release of new version 1.4.1