security/clamav: Update to 0.103.2

Changes: https://blog.clamav.net/2021/04/clamav-01032-security-patch-release.html

PR: 254862
Submitted by: Yasuhiro Kimura <yasu AT utahime DOT org> (maintainer)

(cherry picked from commit e01c3f0b80b378d8e5e2c9ec9c544c291c300556)