Upgrade Nginx to 1.20.1

[wzshiming]

What this PR does / why we need it:

Updating NGINX for a DNS Resolver Vulnerability (CVE-2021-23017)
https://www.nginx.com/blog/updating-nginx-dns-resolver-vulnerability-cve-2021-23017/

nginx/nginx@release-1.19.6...release-1.20.1

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Which issue/s this PR fixes

fixes #7164

How Has This Been Tested?

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

[k8s-ci-robot]

@strongjz: The /test command needs one or more targets.
The following commands are available to trigger jobs:

• /test pull-ingress-nginx-boilerplate
• /test pull-ingress-nginx-codegen
• /test pull-ingress-nginx-gofmt
• /test pull-ingress-nginx-golint
• /test pull-ingress-nginx-lualint
• /test pull-ingress-nginx-chart-lint
• /test pull-ingress-nginx-test-lua
• /test pull-ingress-nginx-test
• /test pull-ingress-nginx-e2e-1-16
• /test pull-ingress-nginx-e2e-1-17
• /test pull-ingress-nginx-e2e-1-18
• /test pull-ingress-nginx-e2e-1-19
• /test pull-ingress-nginx-e2e-helm-chart

Use /test all to run the following jobs:

• pull-ingress-nginx-boilerplate

In response to this:

/test

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[strongjz]

/test all

[tao12345666333]

/lgtm

[strongjz]

/lgtm
/assign @ElvinEfendi

[rikatz]

/approve

Let's merge this and see what happens with e2e tests next

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: rikatz, strongjz, tao12345666333, wzshiming

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