Backport of [NET-5574] Update Go version to 1.20.8 into release/1.14.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #18742 to be assessed for backporting due to the inclusion of the label backport/1.14.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
you will see a blank no-op commit below. If at least one commit succeeded, you
will see the cherry-picked commits up to, not including, the commit where
the merge conflict occurred.

The person who merged in the original PR is:
@zalimeni
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: POST https://api.github.com/repos/hashicorp/consul/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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This resolves several CVEs:

• CVE-2023-39320: cmd/go: go.mod toolchain directive allows arbitrary execution
• CVE-2023-39318: html/template: improper handling of HTML-like comments within script contexts
• CVE-2023-39319: html/template: improper handling of special tags within script contexts
• CVE-2023-39321 and CVE-2023-39322: crypto/tls: panic when processing post-handshake message on QUIC connections

Description

Resolves CVEs and brings us up to the latest version of Go.

Testing & Reproduction steps

Tests should continue to pass.

Links

• https://groups.google.com/g/golang-announce/c/Fm51GRLNRvM

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• d2a0fe8

[hashicorp-cla]

All committers have signed the CLA.

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR

[zalimeni]

Conflict resolved; missing build job in 1.14.x had to be removed from cherry-pick change.