Use a more obvious version and reorder imports

Signed-off-by: Hritik Vijay <hritikxx8@gmail.com>

Author: Hritik14

vulnerabilities/helpers.py

@@ -167,7 +167,7 @@ def __lt__(self, other):
     return affected_package_with_patched_package_objects
 
 
-def split_markdown_front_matter(text: str) -> Tuple[str, str]:
+def split_markdown_front_matter(lines: str) -> Tuple[str, str]:
     r"""
     Split text into markdown front matter and the markdown body
     Return ("", text) for text with non existing front matter
@@ -180,15 +180,19 @@ def split_markdown_front_matter(text: str) -> Tuple[str, str]:
     ... # Markdown starts here
     ... '''
     >>> split_markdown_front_matter(text)
-    ('title: DUMMY-SECURITY-2019-001\ndescription: Incorrect access control.\ncves: [CVE-2042-1337]\n', '\n# Markdown starts here\n')
+    ('title: DUMMY-SECURITY-2019-001\ndescription: Incorrect access control.\ncves: [CVE-2042-1337]', '# Markdown starts here\n')
     """
-
-    front_matter = ""
-    body = text
-    text = text.replace("\r\n", "\n")
-    linezero, _, text = text.partition("---\n")
-
-    if not linezero:  # nothing before first ---
-        front_matter, _, body = text.partition("---")
-
-    return front_matter, body
+    fmlines = []
+    mdlines = []
+    splitter = mdlines
+
+    lines = lines.replace("\r\n", "\n")
+    for index, line in enumerate(lines.split("\n")):
+        if index == 0 and line.strip().startswith("---"):
+            splitter = fmlines
+        elif line.strip().startswith("---"):
+            splitter = mdlines
+        else:
+            splitter.append(line)
+
+    return "\n".join(fmlines), "\n".join(mdlines)

vulnerabilities/importers/istio.py

@@ -31,9 +31,10 @@
 
 from vulnerabilities.data_source import Advisory
 from vulnerabilities.data_source import GitDataSource
+from vulnerabilities.data_source import Reference
+from vulnerabilities.helpers import nearest_patched_package
 from vulnerabilities.helpers import split_markdown_front_matter
 from vulnerabilities.package_managers import GitHubTagsAPI
-from vulnerabilities.helpers import nearest_patched_package
 
 is_release = re.compile(r"^[\d.]+$", re.IGNORECASE).match