chores: run cargo +1.40.0 fmt

Apparently fmt from 1.40.0 is a bit more strict in some places

Let me know if this is worthwhile merging :)

Cargo.lock

@@ -2181,7 +2181,7 @@ dependencies = [
 name = "uu_relpath"
 version = "0.0.4"
 dependencies = [
- "getopts",
+ "clap",
  "uucore",
  "uucore_procs",
 ]

src/uu/stdbuf/src/stdbuf.rs

@@ -80,7 +80,8 @@ fn print_version() {
 fn print_usage(opts: &Options) {
     let brief = "Run COMMAND, with modified buffering operations for its standard streams\n \
                  Mandatory arguments to long options are mandatory for short options too.";
-    let explanation = "If MODE is 'L' the corresponding stream will be line buffered.\n \
+    let explanation =
+        "If MODE is 'L' the corresponding stream will be line buffered.\n \
          This option is invalid with standard input.\n\n \
          If MODE is '0' the corresponding stream will be unbuffered.\n\n \
          Otherwise MODE is a number which may be followed by one of the following:\n\n \

tests/common/util.rs

@@ -135,9 +135,7 @@ impl CmdResult {
     pub fn tmpd(&self) -> Rc<TempDir> {
         match &self.tmpd {
             Some(ptr) => ptr.clone(),
-            None => {
-                panic!("Command not associated with a TempDir")
-            }
+            None => panic!("Command not associated with a TempDir"),
         }
     }