Add more linters to improve code readability (#19989)

Add nakedret, unconvert, wastedassign, stylecheck and nolintlint linters to improve code readability

- nakedret - https://github.com/alexkohler/nakedret - nakedret is a Go static analysis tool to find naked returns in functions greater than a specified function length.
- unconvert - https://github.com/mdempsky/unconvert - Remove unnecessary type conversions
- wastedassign - https://github.com/sanposhiho/wastedassign -  wastedassign finds wasted assignment statements.
- notlintlint -  Reports ill-formed or insufficient nolint directives
- stylecheck - https://staticcheck.io/docs/checks/#ST - keep style consistent
  - excluded: [ST1003 - Poorly chosen identifier](https://staticcheck.io/docs/checks/#ST1003) and [ST1005 - Incorrectly formatted error string](https://staticcheck.io/docs/checks/#ST1005)

integrations/repo_fork_test.go

@@ -45,7 +45,7 @@ func testRepoFork(t *testing.T, session *TestSession, ownerName, repoName, forkO
 		"uid":       fmt.Sprintf("%d", forkOwner.ID),
 		"repo_name": forkRepoName,
 	})
-	resp = session.MakeRequest(t, req, http.StatusSeeOther)
+	session.MakeRequest(t, req, http.StatusSeeOther)
 
 	// Step4: check the existence of the forked repo
 	req = NewRequestf(t, "GET", "/%s/%s", forkOwnerName, forkRepoName)