build(deps): bump nix from 0.19.1 to 0.20.0

Bumps [nix](https://github.com/nix-rust/nix) from 0.19.1 to 0.20.0.
- [Release notes](https://github.com/nix-rust/nix/releases)
- [Changelog](https://github.com/nix-rust/nix/blob/master/CHANGELOG.md)
- [Commits](https://github.com/nix-rust/nix/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Cargo.lock

@@ -95,7 +95,7 @@ dependencies = [
  "lazycell",
  "libc",
  "mach",
- "nix",
+ "nix 0.19.1",
  "num-traits",
  "uom",
  "winapi",
@@ -698,6 +698,18 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "nix"
+version = "0.20.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa9b4819da1bc61c0ea48b63b7bc8604064dd43013e7cc325df098d49cd7c18a"
+dependencies = [
+ "bitflags 1.2.1",
+ "cc",
+ "cfg-if 1.0.0",
+ "libc",
+]
+
 [[package]]
 name = "notify-rust"
 version = "4.2.2"
@@ -1304,7 +1316,7 @@ dependencies = [
  "indexmap",
  "log",
  "native-tls",
- "nix",
+ "nix 0.20.0",
  "notify-rust",
  "once_cell",
  "open",

Cargo.toml

@@ -84,7 +84,7 @@ winapi = { version = "0.3.9", features = [
 ] }
 
 [target.'cfg(not(windows))'.dependencies]
-nix = "0.19.1"
+nix = "0.20.0"
 
 [build-dependencies]
 shadow-rs = "0.5.24"