Add regression test for #5288 (#8385)

doc/whatsnew/fragments/5288.false_positive

@@ -0,0 +1,4 @@
+Fix various false positives for functions that return directly from
+structural pattern matching cases.
+
+Closes #5288

tests/functional/u/unpacking/unpacking_non_sequence_py310.py

@@ -0,0 +1,11 @@
+"""Test returns from structural pattern matching cases."""
+
+def unpack(num) -> tuple[int, int]:
+    """Return a tuple of integers."""
+    match num:
+        case 1:
+            return 1, 1
+        case _:
+            return 0, 0
+
+x, y = unpack(1)

tests/functional/u/unpacking/unpacking_non_sequence_py310.rc

@@ -0,0 +1,2 @@
+[testoptions]
+min_pyver=3.10