[TASK] Drop getLineNo() from the Renderable interface (#1038)

The concept of being able to get rendered is logically independent
from having a position in the input stream.

Hence, both concepts should not be conflated in the
`Renderable` interface.

(We might want to add a dedicated interface for classes that
are linked to specific points in the input stream later, though.)

Author: oliverklee

CHANGELOG.md

@@ -39,6 +39,7 @@ Please also have a look at our
 
 ### Removed
 
+- Drop `getLineNo()` from the `Renderable` interface (#1038)
 - Remove `OutputFormat::level()` (#874)
 - Remove expansion of shorthand properties (#838)
 - Remove `Parser::setCharset/getCharset` (#808)

src/Renderable.php

@@ -12,9 +12,4 @@ interface Renderable
     public function __toString(): string;
 
     public function render(OutputFormat $outputFormat): string;
-
-    /**
-     * @return int<0, max>
-     */
-    public function getLineNo(): int;
 }