Remove some now-unused helpers

tests/ServerTest.php

@@ -896,32 +896,10 @@ public function getDefaultPublicKey(): PublicKeyInterface
  return new ECPublicKey($pk);
  }
 
- /** @return mixed[] */
- private function readJsonFile(string $file): array
- {
- return $this->safeDecode($this->safeReadFile($file));
- }
-
  private function safeReadFile(string $file): string
  {
  $body = file_get_contents(__DIR__.'/'.$file);
  assert($body !== false);
  return $body;
  }
-
- /** @return mixed[] */
- private function safeDecode(string $json): array
- {
- $data = json_decode($json, true);
- assert($data !== false);
- return $data;
- }
-
- /** @param mixed[] $data */
- private function safeEncode(array $data): string
- {
- $json = json_encode($data);
- assert($json !== false);
- return $json;
- }
 }