Minor typo in wp_mail function

[reidbusi]

While working on a plugin, I have discovered that wp_mail calls:

\wp-includes\pluggable.php(453):

<?php
$phpmailer->AddAttachment($attachment);

Where the method in the class is...
\wp-includes\class-phpmailer(2506):

<?php
public function addAttachment($path, $name = '', $encoding = 'base64', $type = '', $disposition = 'attachment')

I note that PHP function names are case insensitive:

Note: Function names are case-insensitive, though it is usually good form to call functions as they appear in their declaration.

​User-defined functions

So, this does not affect anything really, other than my OCD. Do with it as you will.

[Soean]

Changes methods form PascalCase to camelCase

[SergeyBiryukov]

In 40363:

Mail: Use correct capitalization for PHPMailer methods in wp_mail().

Props Soean, reidbusi.
Fixes #39702.