build(deps): bump watcher from 1.1.4 to 1.2.0 (#169)

Bumps [watcher](https://github.com/dart-lang/tools/tree/main/pkgs) from 1.1.4 to 1.2.0.
- [Release notes](https://github.com/dart-lang/tools/releases)
- [Commits](https://github.com/dart-lang/tools/commits/watcher-v1.2.0/pkgs)

---
updated-dependencies:
- dependency-name: watcher
  dependency-version: 1.2.0
  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>

pubspec.lock

@@ -1532,10 +1532,10 @@ packages:
     dependency: "direct main"
     description:
       name: watcher
-      sha256: "592ab6e2892f67760543fb712ff0177f4ec76c031f02f5b4ff8d3fc5eb9fb61a"
+      sha256: f52385d4f73589977c80797e60fe51014f7f2b957b5e9a62c3f6ada439889249
       url: "https://pub.dev"
     source: hosted
-    version: "1.1.4"
+    version: "1.2.0"
   web:
     dependency: transitive
     description: