[TASK] Remove the deprecated OutputFormat::level()

This method is an inconsistently-named alias of
`OutputFormat::getIndentationLevel()`.

Fixes #869

Author: oliverklee

CHANGELOG.md

@@ -28,6 +28,7 @@ Please also have a look at our
 
 ### Removed
 
+- Remove `OutputFormat::level()` (#874))
 - Remove expansion of shorthand properties (#838)
 - Remove `Parser::setCharset/getCharset` (#808)
 - Remove `Rule::getValues()` (#582)

src/OutputFormat.php

@@ -291,14 +291,6 @@ public function getFormatter()
         return $this->oFormatter;
     }
 
-    /**
-     * @return int
-     */
-    public function level()
-    {
-        return $this->iIndentationLevel;
-    }
-
     /**
      * Creates an instance of this class without any particular formatting settings.
      */

src/OutputFormatter.php

@@ -208,6 +208,6 @@ private function prepareSpace($sSpaceString): string
      */
     private function indent(): string
     {
-        return \str_repeat($this->oFormat->sIndentation, $this->oFormat->level());
+        return \str_repeat($this->oFormat->sIndentation, $this->oFormat->getIndentationLevel());
     }
 }