feat: added some typing

fix: corrected a regex

Signed-off-by: Paul Horton <phorton@sonatype.com>

requirements/requirement.py

@@ -13,7 +13,7 @@
 VCS_SCHEMES_REGEX = r'|'.join([scheme.replace('+', r'\+') for scheme in VCS_SCHEMES])
 VCS_REGEX = re.compile(
     rf'^(?P<scheme>{VCS_SCHEMES_REGEX})://((?P<login>[^/@]+)@)?'
-    r'(?P<path>[^#@]+)@(?P<revision>[^#]+))?(#(?P<fragment>\S+))?'
+    r'(?P<path>[^#@]+)(@(?P<revision>[^#]+))?(#(?P<fragment>\S+))?'
 )
 
 # This matches just about everything
@@ -51,7 +51,7 @@ class Requirement(object):
       (eg. "mymodule>1.5,<1.6" => [('>', '1.5'), ('<', '1.6')])
     """
 
-    def __init__(self, line):
+    def __init__(self, line: str) -> None:
         # Do not call this private method
         self.line = line
         self.editable = False
@@ -65,13 +65,13 @@ def __init__(self, line):
         self.revision = None
         self.hash_name = None
         self.hash = None
-        self.extras = []
-        self.specs = []
+        self.extras: list[str] = []
+        self.specs: list[str] = []
 
-    def __repr__(self):
+    def __repr__(self) -> str:
         return '<Requirement: "{0}">'.format(self.line)
 
-    def __getitem__(self, key):
+    def __getitem__(self, key: str) -> str:
         return getattr(self, key)
 
     def __eq__(self, other):