Update snapd warning after official deprecation

[TraceyC77]

In #4632 we updated the wording when a user runs snaps

      echo -e "${YELLOW}WARNING:${NC} snap is running with ${CONFINEMENT} confinement." \
        "Snaps will stop working in early January 2025. See ${URL} for details"

Remove "Snaps will stop working" (they will still work if installed manually
Update to indicate snaps are not supported

Suggested:

      echo -e "${YELLOW}WARNING:${NC} snap is running with ${CONFINEMENT} confinement." \
        "Snaps are no longer supported on Solus as of January 2025. See ${URL} for details"

Update it on the Help Center as well
getsolus/help-center-docs#592