Fix missing-param-doc FP

doc/whatsnew/fragments/7827.false_positive

@@ -0,0 +1,3 @@
+Fix ``missing-param-doc`` false positive when function parameter has escaped underscore.
+
+Closes #7827

pylint/extensions/_check_docs_utils.py

@@ -644,16 +644,13 @@ def match_param_docs(self) -> tuple[set[str], set[str]]:
         entries = self._parse_section(self.re_param_section)
         entries.extend(self._parse_section(self.re_keyword_param_section))
         for entry in entries:
+            # Remove escape characters necessary for asterisks and trailing underscores
+            entry = entry.replace("\\", "")
             match = self.re_param_line.match(entry)
             if not match:
                 continue
 
-            param_name = match.group(1)
-            # Remove escape characters necessary for asterisks
-            param_name = param_name.replace("\\", "")
-
-            param_type = match.group(2)
-            param_desc = match.group(3)
+            param_name, param_type, param_desc = match.groups()
 
             if param_type:
                 params_with_type.add(param_name)

tests/functional/ext/docparams/parameter/missing_param_doc_required_Google.py

@@ -433,3 +433,15 @@ def test_finds_multiple_complex_types_google(
         named_arg_nine,
         named_arg_ten,
     )
+
+def test_escape_underscore(something: int, raise_: bool = False) -> bool:
+    """Tests param with _ is handled correctly.
+
+    Args:
+        something: the something
+        raise\\_: the other
+
+    Returns:
+        something
+    """
+    return something and raise_