Bump x11-dl from 2.19.1 to 2.21.0

Bumps [x11-dl](https://github.com/AltF02/x11-rs) from 2.19.1 to 2.21.0.
- [Release notes](https://github.com/AltF02/x11-rs/releases)
- [Changelog](https://github.com/AltF02/x11-rs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/AltF02/x11-rs/compare/v2.19.1...v2.21.0)

---
updated-dependencies:
- dependency-name: x11-dl
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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

Cargo.lock

@@ -7666,12 +7666,12 @@ dependencies = [
 
 [[package]]
 name = "x11-dl"
-version = "2.19.1"
+version = "2.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea26926b4ce81a6f5d9d0f3a0bc401e5a37c6ae14a1bfaa8ff6099ca80038c59"
+checksum = "38735924fedd5314a6e548792904ed8c6de6636285cb9fec04d5b1db85c1516f"
 dependencies = [
- "lazy_static",
  "libc",
+ "once_cell",
  "pkg-config",
 ]