Deprecate Debian Stretch in Vulnerability Detector

[MarcelKemp]

Related issue
#5515

Description

This PR removes all references to Debian Stretch found in the Vulnerability Scanner. This change must be applied with the changes performed in wazuh/wazuh#14542.

Checks

• [x] It compiles without warnings.
• [x] Spelling and grammar.
• [x] Used impersonal speech.
• [x] Used uppercase only on nouns.