Auto merge of #6760 - rust-lang:dependabot/cargo/toml-0.5.0, r=dwijnand

Update toml requirement from 0.4.2 to 0.5.0

Updates the requirements on [toml](https://github.com/alexcrichton/toml-rs) to permit the latest version.
<details>
<summary>Release notes</summary>

*Sourced from [toml's releases](https://github.com/alexcrichton/toml-rs/releases).*

> ## Preserve order feature, minor fixes
> - Add `preserve_order` Cargo feature. This retains the order of map keys in `toml::Value`. ([#278](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/278))
> - Fix issue [#279](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/279) where some duplicate table headers were accepted. Added `Deserializer::set_allow_duplicate_after_longer_table` for anyone who wants to retain the old, broken behavior. ([#280](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/280))
> - Fix case sensitivity with T, Z, and E. ([#290](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/290))
> - Add `PartialEq` to `de::Error`. ([#292](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/292))
</details>
<details>
<summary>Commits</summary>

- [`dbdcc9c`](toml-rs/toml-rs@dbdcc9c) Merge pull request [#292](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/292) from omarabid/master
- [`fbc0557`](toml-rs/toml-rs@fbc0557) Add PartialEq to Toml::de
- [`4fb12b4`](toml-rs/toml-rs@4fb12b4) Merge pull request [#290](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/290) from ehuss/fix-case-sensitivity
- [`8fce90e`](toml-rs/toml-rs@8fce90e) Fix case sensitivity with T, Z, and E.
- [`56f9afb`](toml-rs/toml-rs@56f9afb) Merge pull request [#278](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/278) from Kerollmops/master
- [`d0977ab`](toml-rs/toml-rs@d0977ab) Merge pull request [#280](https://github-redirect.dependabot.com/alexcrichton/toml-rs/issues/280) from alexcrichton/fix-duplicate
- [`7ee1c1b`](toml-rs/toml-rs@7ee1c1b) Fix disallowing duplicate table headers
- [`ad5ea1d`](toml-rs/toml-rs@ad5ea1d) Update build urls
- [`600c6e5`](toml-rs/toml-rs@600c6e5) Tweak travis config
- [`0372ba6`](toml-rs/toml-rs@0372ba6) Update the serde test-suite map! macro
- Additional commits viewable in [compare view](toml-rs/toml-rs@0.4.2...0.5.0)
</details>
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Cargo.toml

@@ -56,7 +56,7 @@ shell-escape = "0.1.4"
 tar = { version = "0.4.18", default-features = false }
 tempfile = "3.0"
 termcolor = "1.0"
-toml = "0.4.2"
+toml = "0.5.0"
 url = "1.1"
 url_serde = "0.2.0"
 walkdir = "2.2"