Fixed sprintf format strings (#6)

$lineNumber is a string; it is the result of a call to sprintf(). (Hungarian notation helps with such stuff ...)

Author: Alien426

src/SimpleDiff.php

@@ -34,10 +34,10 @@ public function compare(string $left, string $right, bool $strict = false): Diff
 					}
 					$captureBuffer = [];
 				}
-				$return[] = sprintf('  %d%s', $lineNumber, $original);
+				$return[] = sprintf('  %s%s', $lineNumber, $original);
 			} else {
-				$captureBuffer['-'][] = sprintf('- %d%s', $lineNumber, $this->prettyRender($original));
-				$captureBuffer['+'][] = sprintf('+ %d%s', $lineNumber, $this->prettyRender($target));
+				$captureBuffer['-'][] = sprintf('- %s%s', $lineNumber, $this->prettyRender($original));
+				$captureBuffer['+'][] = sprintf('+ %s%s', $lineNumber, $this->prettyRender($target));
 				$changedLines[] = $i + 1;
 			}
 		}