Remove consecutive whitespace when comparing tests

As discussed previously php-mf2 has custom handling of textContent to
match with what consumers were expecting to get back. This means all
tests around plain text output have a high tendency to fail.

This change addresses that a little by ignoring whitespace differences
within e-* properties.

tests/Mf2/MicroformatsTestSuiteTest.php

@@ -48,6 +48,9 @@ public function testMixedFromTestSuite($input, $expectedOutput)
      * * We sort arrays by key, normalising them, because JSON objects are unordered.
      * * We json_encode strings, and cut the starting and ending ", so PHPUnit better
      *   shows whitespace characters like tabs and newlines.
+     * * We replace all consecutive whitespace with single space characters in e-* value
+     *   properties, to avoid failing tests only because difference in the handing of
+     *   extracting textContent.
      **/
     public function makeComparible($array)
     {
@@ -56,6 +59,9 @@ public function makeComparible($array)
             if (gettype($value) === 'array') {
                 $array[$key] = $this->makeComparible($value);
             } else if (gettype($value) === 'string') {
+                if ($key === 'value' && array_key_exists('html', $array)) {
+                    $value = preg_replace('/\s+/', ' ', $value);
+                }
                 $array[$key] = substr(json_encode($value), 1, -1);
             }
         }