Update NGINX Ingress Controller image to v1.3.1

What does this MR do?

Note: depends on gitlab-org/cloud-native/mirror/images!9 (merged).

Updates the NGINX Ingress Controller image default value to v1.3.1.

Reference to last change of this kind: !2843 (merged)

Related issues

Closes #4856 (closed)

Testing notes

#4856 (comment 1460919305)

v1.3.1 release notes say:

v1.3.0 is a safe transition version, using v1.3.0 can automatically complete the merging of election locks, and then you can safely upgrade to v1.3.1.

However, I didn't have any problem updating directly from 1.2.1 to 1.3.1.

I tested by:

1. Deploying current version of chart (from master or latest release from Helm repo)
2. Watching logs from NGINX (stern -n gitlab -l app=nginx-ingress)
3. Deploying chart from this MR branch
4. Saving Ingress to YAML file (kubectl get ingress -oyaml)
5. Deleting Ingress from cluster
6. Applying Ingress from YAML file
7. Ensuring NGINX picks it up and assigns it an IP address

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion.

Required

• Merge Request Title and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com
• When ready for review, MR is labeled "~workflow::ready for review" per the Distribution MR workflow

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for omnibus-gitlab opened
• Validate potential values for new configuration settings. Formats such as integer 10, duration 10s, URI scheme://user:passwd@host:port may require quotation or other special handling when rendered in a template and written to a configuration file.

Closes #4856 (closed)