[ci] upgrade GitHub Actions third-party actions to newest versions

[jameslamb]

I've been noticing a bunch of these warnings in GitHub Actions jobs:

The add-path command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/

The set-env command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/

For example, you can see these annotations on https://github.com/microsoft/LightGBM/actions/runs/343069981.

To be sure that these changes from GitHub don't disrupt our CI, this PR updates the GitHub Actions workflows in this project to use the newest versions of third-party actions. You can see, specifically, that updates to deal with this deprecation were made in the most recent release of actions/checkout: https://github.com/actions/checkout/releases/tag/v2.3.4

It also fixes a mistake I made setting them up....we should be using https://github.com/conda-incubator/setup-miniconda, not this fork of it: https://github.com/goanpeca/setup-miniconda.

[StrikerRUS]

Please update this line as well.

LightGBM/.github/workflows/cuda.yml

Line 41 in 12e220b

uses: actions/checkout@v1

[jameslamb]

Please update this line as well.

LightGBM/.github/workflows/cuda.yml

Line 41 in 12e220b

uses: actions/checkout@v1

ah missed that one!

[jameslamb]

/gha run r-valgrind

[jameslamb]

looks like valgrind is happy with this change. I did check before that the image we use for valgrind tests had a recent version of git in it, and it does.

https://github.com/microsoft/LightGBM/runs/1349685476?check_suite_focus=true

[StrikerRUS]

Thanks! Just one minor comment below.

[github-actions]

This pull request has been automatically locked since there has not been any recent activity since it was closed. To start a new related discussion, open a new issue at https://github.com/microsoft/LightGBM/issues including a reference to this.