downloading HD covers error

[rcyggdra]

Unpublished books encountered errors while downloading HD covers, which prevented the download of trial content.

e.g. https://bookwalker.jp/de248a3d6a-7eb6-4231-944c-6d264c409c52/

E:\Media\BW-preview-DLer>python bookrunner.py de248a3d6a-7eb6-4231-944c-6d264c409c52

Downloading 佐々木とピーちゃん ８ 巡り巡って舞台は学校、みんなで仲良くラブコメ回 ～真実の愛を手にするのは誰だ？～【電子 特典付き】's preview files...
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Downloading metadata
Downloading HD cover
Traceback (most recent call last):
  File "E:\Media\BW-preview-DLer\bookrunner.py", line 78, in <module>
    cover_str = re.search(r'<meta property="og:image" content="https://c.bookwalker.jp/(\d+)/t_700x780.jpg">', cover_response.text).group(1)
AttributeError: 'NoneType' object has no attribute 'group'

Request: Fix errors in cover download or skip cover download

thank you

[CeIest]

Fixed here! Thanks for the report~