upgrade golangci version used to v1.23.3

Author: camilamacedo86

.travis.yml

@@ -29,7 +29,7 @@ script: ./test.sh
 jobs:
   include:
     - stage: linting
-      before_script: curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.21.0
+      before_script: curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.23.3
       script: ./scripts/verify.sh
 
     - stage: golden