lang/go121: Update to 1.21.8

MFH: 2024Q1
Security: b1b039ec-dbfc-11ee-9165-901b0e9408dc
Security: CVE-2023-24783
Security: CVE-2023-45290
Security: CVE-2023-45289
Security: CVE-2024-24785
Security: CVE-2024-24784
(cherry picked from commit e63c7e0d9830902f0b45d304b41d05be8c8b221c)