[bellazon] improve video URL regex (#8392)

match <source> elements with attributes before 'src="..."'

gallery_dl/extractor/bellazon.py

@@ -27,7 +27,7 @@ class BellazonExtractor(Extractor):
         native = (f"{self.root}/", f"{self.root[6:]}/")
         extract_urls = text.re(
             r'(?s)<('
-            r'(?:video .*?<source src|a [^>]*?href)="([^"]+).*?</a>'
+            r'(?:video .*?<source [^>]*?src|a [^>]*?href)="([^"]+).*?</a>'
             r'|img [^>]*?src="([^"]+)"[^>]*>'
             r')'
         ).findall

test/results/bellazon.py

@@ -204,6 +204,16 @@ __tests__ = (
     "#results" : "https://www.bellazon.com/main/uploads/monthly_2018_04/30602369_1891291154222843_1650952189830496256_n.jpg.33e6ab78dd0e8723f790ad4f58f3761a.jpg",
 },
 
+{
+    "#url"     : "https://www.bellazon.com/main/topic/70367-elyzaveta-kovalenko/page/5/#comment-5464973",
+    "#comment" : "(#8392)",
+    "#class"   : bellazon.BellazonPostExtractor,
+    "#results" : (
+        "https://www.bellazon.com/main/uploads/monthly_2022_05/917305269_LizaKovalenko-Instagram2021_04_19.mp4.467d190a54e1bcabc50767a69706501d.mp4",
+        "https://www.bellazon.com/main/uploads/monthly_2022_05/2027180206_LizaKovalenko-Instagram2021_04_23.mp4.2eae87d7e9d6f1a993611fa1f73e8e7b.mp4",
+    ),
+},
+
 {
     "#url"     : "https://www.bellazon.com/main/topic/57872-millie-brady/",
     "#class"   : bellazon.BellazonThreadExtractor,