Update beautifulsoup4 requirement from ==4.12.* to ==4.13.* (#4804)

* Update beautifulsoup4 requirement from ==4.12.* to ==4.13.*

Updates the requirements on [beautifulsoup4](https://www.crummy.com/software/BeautifulSoup/bs4/) to permit the latest version.

---
updated-dependencies:
- dependency-name: beautifulsoup4
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

* Replace findAll with find_all

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Raphael Michel <michel@rami.io>

src/pretix/base/services/mail.py

@@ -674,7 +674,7 @@ def replace_images_with_cid_paths(body_html):
     if body_html:
         email = BeautifulSoup(body_html, "lxml")
         cid_images = []
-        for image in email.findAll('img'):
+        for image in email.find_all('img'):
             original_image_src = image['src']
 
             try:

src/tests/base/__init__.py

@@ -74,7 +74,7 @@ def extract_form_fields(soup):
             continue
 
     # textareas
-    for textarea in soup.findAll('textarea'):
+    for textarea in soup.find_all('textarea'):
         if textarea['name'] in data:
             if not isinstance(data[textarea['name']], list):
                 data[textarea['name']] = [data[textarea['name']]]