[FIX] core: remove email escape logic from html_sanitize.

Related to #30326

Before #30326, when calling html_sanitize, some content may be escaped
when it shouldn't. A simple example was images with cid links containing @.
(a first fix for another use case was made in 8aff53733b)

We suspect that this escaping (added in 71a92f46e4)
was made to avoid loosing email with format '<email@domaine>' in html_sanitize
to escape them if html_sanitize is called on plain text.

Anyway, only html should be passed to html_sanitize, and therefore email of format
<email@domain> should already be escaped.

PR #30326 fixes the unwanted behaviour in 12.0 and this commit removes
this logic in master.

closes odoo/odoo#30815

odoo/addons/base/tests/test_mail.py

@@ -92,16 +92,6 @@ class TestSanitizer(unittest.TestCase):
         for attr in ['javascript']:
             self.assertNotIn(attr, sanitized_html, 'html_sanitize did not remove enough unwanted attributes')
 
-    def test_sanitize_escape_emails(self):
-        emails = [
-            "Charles <charles.bidule@truc.fr>",
-            "Dupuis <'tr/-: ${dupuis#$'@truc.baz.fr>",
-            "Technical <service/technical+2@open.com>",
-            "Div nico <div-nico@open.com>"
-        ]
-        for email in emails:
-            self.assertIn(misc.html_escape(email), html_sanitize(email), 'html_sanitize stripped emails of original html')
-
     def test_sanitize_unescape_emails(self):
         not_emails = [
             '<blockquote cite="mid:CAEJSRZvWvud8c6Qp=wfNG6O1+wK3i_jb33qVrF7XyrgPNjnyUA@mail.gmail.com" type="cite">cat</blockquote>',

odoo/tools/mail.py

@@ -176,11 +176,6 @@ def html_sanitize(src, silent=True, sanitize_tags=True, sanitize_attributes=Fals
 
     logger = logging.getLogger(__name__ + '.html_sanitize')
 
-    # html encode email tags
-    part = re.compile(r"(<(([^a<>]|a[^<>\s])[^<>]*)@[^<>]+>)", re.IGNORECASE | re.DOTALL)
-    # remove results containing cite="mid:email_like@address" (ex: blockquote cite)
-    # cite_except = re.compile(r"^((?!cite[\s]*=['\"]).)*$", re.IGNORECASE)
-    src = part.sub(lambda m: (u'cite=' not in m.group(1) and u'alt=' not in m.group(1) and u'src=' not in m.group(1)) and misc.html_escape(m.group(1)) or m.group(1), src)
     # html encode mako tags <% ... %> to decode them later and keep them alive, otherwise they are stripped by the cleaner
     src = src.replace(u'<%', misc.html_escape(u'<%'))
     src = src.replace(u'%>', misc.html_escape(u'%>'))