[DevOps]: Update `setup-miniconda` in `publish-docs` to fix doc build failure

[tomvothecoder]

What happened?

setup-miniconda should be updated from v2 to v3

e3sm_diags/.github/workflows/build_workflow.yml

Lines 139 to 147 in 7692014

	- name: Set up Conda Environment
	uses: conda-incubator/setup-miniconda@v2
	with:
	activate-environment: "e3sm_diags_ci"
	miniforge-variant: Miniforge3
	miniforge-version: latest
	environment-file: conda-env/ci.yml
	channel-priority: strict
	auto-update-conda: true

What did you expect to happen? Are there are possible answers you came across?

No response

Minimal Complete Verifiable Example (MVCE)

Relevant log output

Anything else we need to know?

No response

Environment

Latest main