these 3 linters were deprecated in favor of unused

Signed-off-by: Andre Ferraz <[email protected]>

Author: Andre Ferraz

.golangci.yml

@@ -7,13 +7,11 @@ run:
 linters:
   enable:
     - vet
-    - deadcode
     - goimports
-    - varcheck
-    - structcheck
     - ineffassign
     - unconvert
     - unparam
+    - unused
 linters-settings:
   goimports:
     local-prefixes: github.com/argoproj-labs/argocd-image-updater