chore: refactor Lint Configuration for Go Project

- Remove `deadcode`, `depguard`, `structcheck`, and `varcheck` linters from the `.golangci.yml` configuration

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

.golangci.yml

@@ -4,8 +4,6 @@ linters:
   fast: false
   enable:
     - bodyclose
-    - deadcode
-    - depguard
     - dogsled
     - dupl
     - errcheck
@@ -29,13 +27,11 @@ linters:
     - nolintlint
     - rowserrcheck
     - staticcheck
-    - structcheck
     - stylecheck
     - typecheck
     - unconvert
     - unparam
     - unused
-    - varcheck
     - whitespace
     - gofumpt