Fix information about CVE-2023-47235 on website

[dpward]

The security page shows that CVE-2023-47235 affects FRR versions "< 9.0.1", which is wrong: it was fixed in 9.0.2 (and also in 8.5.4). Please change this to read "< 8.5.4, 9.0.0 ~ 9.0.1".

Also there were four CVEs here, not one. Can we list all the numbers please? The commits on this page actually correspond (in order) to:

• CVE-2023-47234
• CVE-2023-47235
• CVE-2023-46752
• CVE-2023-46753

[ton31337]

Splitted FRRouting/frr-www#63.