getArtifact function using deprecated (due to security and usability issues) buffer function

[twalshOG]

Describe the bug Receive a deprecation warning when using downloading an artifact

To Reproduce Steps to reproduce the behavior:

1. Use the the downloadArtifact functionality in a Github actions pipeline
2. Note you get the following error

(node:1671) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead. (Use node --trace-deprecation ... to show where the warning was created)

Code producing the warning

import * as artifact from '@actions/artifact';
.........
  const response = await artifact.default.getArtifact(artifactName);
  const artifactClient = artifact.default;
  await artifactClient.downloadArtifact(response.artifact.id, {
    path: downloadFolder,
  });

Expected behavior Would not get the error. This error is due to the fact that @actions/artifact is depending on archiver 5.3.1 which in turn depends on archiver-utils 2.1.0 which use using the depreciated buffer call.

Screenshots

**Where produced **

• Github Actions Agent: ubuntu-latest
• Node version: Default version installed on ubuntu-latest

Additional context Updating to a new version (3.0.0 or above) would address this issue. The fix/update to this was already released for archiver-utils.

[TWiStErRob]

To finish the amazing investigation, and give actionable steps for this project:

https://github.com/actions/toolkit/blob/5430c5d84832076372990c7c27f900878ff66dc9/packages/artifact/package.json#L52

The above line needs to be updated from 5.3.1 to at least 6.0.0, which doesn't look like a big jump, as the only breaking change listed is dropping Node 10. 6.0.0 uses archiver-utils 3.0.0.

• (https://github.com/actions/toolkit/pull/1633 would eventually solve this, but there's no reason to wait for that.)

[hubert-rutkowski85]

Bump - it seems like a simple and useful change.

[twalshOG]

This bug was addressed in https://github.com/actions/toolkit/pull/1712