ci: rename Go 1.21 option back to ubuntu-latest

Documentation expects it to be named ubuntu-latest.

Author: pi-alexander-popel

ci/options.json

@@ -14,7 +14,7 @@
     "PackageRequirement": true
   },
   {
-    "Name": "ubuntu-go-1.21",
+    "Name": "ubuntu-latest-go-1.21",
     "Image": "ubuntu-latest",
     "Language": "go",
     "LanguageVersion": "1.21",