Bump once_cell from 1.7.2 to 1.8.0 (#255)

Bumps [once_cell](https://github.com/matklad/once_cell) from 1.7.2 to 1.8.0.
- [Release notes](https://github.com/matklad/once_cell/releases)
- [Changelog](https://github.com/matklad/once_cell/blob/master/CHANGELOG.md)
- [Commits](https://github.com/matklad/once_cell/compare/v1.7.2...v1.8.0)

---
updated-dependencies:
- dependency-name: once_cell
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>

Cargo.lock

@@ -558,9 +558,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.7.2"
+version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af8b08b04175473088b46763e51ee54da5f9a164bc162f615b91bc179dbf15a3"
+checksum = "692fcb63b64b1758029e0a96ee63e049ce8c5948587f2f7208df04625e5f6b56"
 
 [[package]]
 name = "parking_lot"

helix-core/Cargo.toml

@@ -22,7 +22,7 @@ unicode-width = "0.1"
 unicode-general-category = "0.4.0"
 # slab = "0.4.2"
 tree-sitter = "0.19"
-once_cell = "1.4"
+once_cell = "1.8"
 regex = "1"
 
 serde = { version = "1.0", features = ["derive"] }

helix-term/Cargo.toml

@@ -23,7 +23,7 @@ helix-view = { path = "../helix-view", features = ["term"]}
 helix-lsp = { path = "../helix-lsp"}
 
 anyhow = "1"
-once_cell = "1.4"
+once_cell = "1.8"
 
 tokio = { version = "1", features = ["full"] }
 num_cpus = "1"

helix-view/Cargo.toml

@@ -19,7 +19,7 @@ helix-lsp = { path = "../helix-lsp"}
 # Conversion traits
 tui = { path = "../helix-tui", package = "helix-tui", default-features = false, features = ["crossterm"], optional = true }
 crossterm = { version = "0.20", features = ["event-stream"], optional = true }
-once_cell = "1.4"
+once_cell = "1.8"
 url = "2"
 
 tokio = { version = "1", features = ["full"] }