fix(ci): correct coverage upload format to go-coverprofile

The datadog-ci CLI expects 'go-coverprofile' not 'go-cover'.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: platinummonkey

.github/workflows/ci.yml

@@ -120,7 +120,7 @@ jobs:
           DD_SITE: datadoghq.com
         run: |
           # Upload coverage reports to Datadog
-          datadog-ci coverage upload --format=go-cover coverage.out
+          datadog-ci coverage upload --format=go-coverprofile coverage.out
 
       - name: Check coverage threshold
         run: |