Minor, correct spelling of PKCS8 key format

Summary: I faked this out locally because of the OSX stuff and goofed the
key format spelling.

Auditors: btrahan

src/applications/auth/sshkey/PhabricatorAuthSSHPublicKey.php

@@ -107,14 +107,14 @@ final class PhabricatorAuthSSHPublicKey extends Phobject {
     return $key;
   }
 
-  public function toPCKS8() {
+  public function toPKCS8() {
 
     // TODO: Put a cache in front of this.
 
     $tmp = new TempFile();
     Filesystem::writeFile($tmp, $this->getEntireKey());
     list($pem_key) = execx(
-      'ssh-keygen -e -m pcks8 -f %s',
+      'ssh-keygen -e -m PKCS8 -f %s',
       $tmp);
     unset($tmp);
 

src/applications/conduit/controller/PhabricatorConduitAPIController.php

@@ -224,7 +224,7 @@ final class PhabricatorConduitAPIController
 
       $raw_key = idx($metadata, 'auth.key');
       $public_key = PhabricatorAuthSSHPublicKey::newFromRawKey($raw_key);
-      $ssl_public_key = $public_key->toPCKS8();
+      $ssl_public_key = $public_key->toPKCS8();
 
       // First, verify the signature.
       try {