Moderate: zsh security update (Oracle Linux 8)

[5.5.1-9]
- do not perform PROMPT_SUBST evaluation on file.file/%K arguments (CVE-2021-45444)

[5.5.1-8]
- improve printing of error messages introduced by the fix of CVE-2019-20044

[5.5.1-7]
- drop privileges securely when unsetting PRIVILEGED option (CVE-2019-20044)