dep: Add fmt 9.0.0

dep/fmt/CONTRIBUTING.md

@@ -0,0 +1,20 @@
+Contributing to {fmt}
+=====================
+
+By submitting a pull request or a patch, you represent that you have the right
+to license your contribution to the {fmt} project owners and the community,
+agree that your contributions are licensed under the {fmt} license, and agree
+to future changes to the licensing.
+
+All C++ code must adhere to [Google C++ Style Guide](
+https://google.github.io/styleguide/cppguide.html) with the following
+exceptions:
+
+* Exceptions are permitted
+* snake_case should be used instead of UpperCamelCase for function and type
+  names
+
+All documentation must adhere to the [Google Developer Documentation Style
+Guide](https://developers.google.com/style).
+
+Thanks for contributing!