Auto merge of #196 - rust-lang:dependabot/cargo/env_logger-0.8.4, r=JohnTitor

Bump env_logger from 0.8.3 to 0.8.4

Bumps [env_logger](https://github.com/env-logger-rs/env_logger) from 0.8.3 to 0.8.4.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/env-logger-rs/env_logger/releases">env_logger's releases</a>.</em></p>
<blockquote>
<h2>0.8.4</h2>
<p>Improvements:</p>
<ul>
<li>Allow writing logs to a custom output target (via <code>Target::Pipe</code>)</li>
</ul>
<p>Bug fixes:</p>
<ul>
<li>Actually allow overriding filter levels using <code>env_logger::Builder</code>s methods, as documented</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/env-logger-rs/env_logger/commit/13cafce572362582f57964eae6cb4a41f52fd04a"><code>13cafce</code></a> Bump version to 0.8.4</li>
<li><a href="https://github.com/env-logger-rs/env_logger/commit/090081156127dcd896b8b00837549cb4008c43d0"><code>0900811</code></a> Ensure unique directive names when building filters</li>
<li><a href="https://github.com/env-logger-rs/env_logger/commit/1a8379a533f043e623d5eb4a898d171927ad61c1"><code>1a8379a</code></a> Allow writing logs to a custom output target (Target::Pipe)</li>
<li><a href="https://github.com/env-logger-rs/env_logger/commit/2151771ffd1e4c8e20ed6070ab49528d85ebcde1"><code>2151771</code></a> Upgrade to GitHub-native Dependabot</li>
<li><a href="https://github.com/env-logger-rs/env_logger/commit/16d982ed979bb9361048fc25a5589ac5e06daf17"><code>16d982e</code></a> Fix lints</li>
<li>See full diff in <a href="https://github.com/env-logger-rs/env_logger/compare/v0.8.3...v0.8.4">compare view</a></li>
</ul>
</details>
<br />

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[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)

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</details>

Author: bors