fix(fmt): doc block trailing whitespace

fmt/src/formatter.rs

@@ -719,7 +719,7 @@ impl<'a, W: Write> Formatter<'a, W> {
                 writeln!(self.buf(), "/**")?;
                 for line in lines {
                     let line = line.trim().trim_start_matches('*').trim_start();
-                    writeln!(self.buf(), " * {line}")?;
+                    writeln!(self.buf(), "{}", format!(" * {line}").trim_end())?;
                 }
                 write!(self.buf(), " */")?;
             } else {

fmt/testdata/DocComments/fmt.sol

@@ -22,7 +22,13 @@ contract HelloWorld {
     /**
      * @dev does nothing
      */
-    function example() public {}
+    function example() public {
+        /**
+         * Does this add a whitespace error?
+         *
+         * Let's find out.
+         */
+    }
 
     /**
      * @dev Calculates a rectangle's surface and perimeter.

fmt/testdata/DocComments/original.sol

@@ -24,7 +24,13 @@ contract HelloWorld {
     }
 
     /** @dev does nothing */
-    function example() public {}
+    function example() public {
+          /**
+     * Does this add a whitespace error?
+    *  
+     * Let's find out.
+     */
+    }
 
     /** @dev Calculates a rectangle's surface and perimeter.
       * @param w Width of the rectangle.