enable err113 linter

.golangci.yml

auth/auth.go

cmd/rednerd/cmd/admin_password.go

engines/wpd/engine.go

engines/wpd/wpd.go

lib/mailsender.go

lib/redner.go

rendering/engine_registry.go

rendering/pooled_engine.go

restapi/handlers/account-template-add.go

restapi/handlers/account-template-preview.go

restapi/handlers/account-template-update.go

restapi/handlers/auth-userinfo.go

restapi/handlers/errors.go

restapi/handlers/render.go

restapi/handlers/template-varlist.go

restapi/handlers/user-apikey-delete.go

restapi/handlers/user-delete.go

restapi/server_.go

utils/http.go