chore: update README.md for v1.4.0 (#1779)

Automated update of `README.md` for release v1.4.0

This pull request was created by
[cgrindel/gha_create_release](https://github.com/cgrindel/gha_create_release).

Co-authored-by: cgrindel <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: 3 people

README.md

@@ -88,7 +88,7 @@ Add a dependency on `rules_swift_package_manager`.
 
 <!-- BEGIN MODULE SNIPPET -->
 ```python
-bazel_dep(name = "rules_swift_package_manager", version = "1.3.0")
+bazel_dep(name = "rules_swift_package_manager", version = "1.4.0")
 ```
 <!-- END MODULE SNIPPET -->