updated vulnerable deps
* Updated signal-hook-registry 1.2.1 to 1.2.2, as it drops dependency on vulnerable arc-swap 0.4.7 https://rustsec.org/advisories/RUSTSEC-2020-0091
* Updated generic-array 0.12.3 to 0.12.4, vuln https://rustsec.org/advisories/RUSTSEC-2020-0146
* Updated sized-chunks 0.6.2 to 0.6.4, vuln https://rustsec.org/advisories/RUSTSEC-2020-0041 fixed in 0.6.3, in 0.6.4 fixed some UB https://github.com/bodil/sized-chunks/blob/master/CHANGELOG.md#064---2021-02-17