bump golang to 1.20.5

Signed-off-by: cpanato <[email protected]>

Author: cpanato

images/gcb-docker-gcloud/README.md

@@ -6,7 +6,7 @@ combination of `docker`, `gcloud`, and `go` all in the same build step
 ## contents
 
 - base:
-  - golang:1.20.3-alpine
+  - golang:1.20.5-alpine
 - languages:
   - `go`
 - tools:

images/gcb-docker-gcloud/cloudbuild.yaml

@@ -14,7 +14,7 @@ steps:
     - gcr.io/$PROJECT_ID/gcb-docker-gcloud:latest
 substitutions:
   _GIT_TAG: '12345'
-  _GO_VERSION: 1.20.3
+  _GO_VERSION: 1.20.5
 images:
   - 'gcr.io/$PROJECT_ID/gcb-docker-gcloud:$_GIT_TAG'
   - 'gcr.io/$PROJECT_ID/gcb-docker-gcloud:latest'