⬆️ Update num requirement from 0.3 to 0.4 (#90)

Updates the requirements on [num](https://github.com/rust-num/num) to permit the latest version.
- [Release notes](https://github.com/rust-num/num/releases)
- [Changelog](https://github.com/rust-num/num/blob/master/RELEASES.md)
- [Commits](rust-num/num@num-0.3.0...num-0.4.0)

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Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

src/yourcontrols/Cargo.toml

@@ -22,7 +22,7 @@ dns-lookup = "1.0"
 indexmap = {version = "1.6", features = ["serde-1"]}
 laminar = {git = "https://github.com/Sequal32/laminar.git"}
 log = "0.4"
-num = "0.3"
+num = "0.4"
 retain_mut = "0.1"
 rmp-serde = "0.15"
 semver = "0.11"