exclude composites from lint checks.

Composites checks prevents using unkeyed fields, which is not needed in the examples project because
`time.Time` is embedded into `github.Timestamp`

Author: zombieleet

.golangci.yml

@@ -21,7 +21,9 @@ linters:
     - staticcheck
     - ineffassign
     - unused
-issues: 
+issues:
+  exclude:
+    - composites
   exclude-rules:
   - linters:
     - dogsled