lint: remove strcutcheck and varcheck

.github/linters/.golangci.yml

@@ -32,12 +32,10 @@ linters:
     - revive
     - rowserrcheck
     - staticcheck
-    - structcheck
     - stylecheck
     - typecheck
     - unconvert
     - unparam
-    - varcheck
     - whitespace
   disable:
     - deadcode