cargo-{clean,fmt}: add page (#10770)

* cargo clean: add page

* cargo fmt: add page

pages/common/cargo-fmt.md

@@ -0,0 +1,16 @@
+# cargo fmt
+
+> Run `rustfmt` on all source files in a Rust project.
+> More information: <https://github.com/rust-lang/rustfmt>.
+
+- Format all source files:
+
+`cargo fmt`
+
+- Check for formatting errors without writing to the files:
+
+`cargo fmt --check`
+
+- Pass arguments to each `rustfmt` call:
+
+`cargo fmt -- {{rustfmt_args}}`