[TYP] Add more literals to MarkerType (matplotlib#30261)

* Update mpl.typing.MarkerType

* Revert superfluous changes

* Moved import

* Remove unnecessary import

Co-authored-by: Tim Hoffmann <2836374+timhoffm@users.noreply.github.com>

* Correct integers values on MarkerType

---------

Co-authored-by: Tim Hoffmann <2836374+timhoffm@users.noreply.github.com>

Author: ZPyrolink

lib/matplotlib/typing.py

@@ -70,7 +70,16 @@
 )
 """See :doc:`/gallery/lines_bars_and_markers/markevery_demo`."""
 
-MarkerType: TypeAlias = str | path.Path | MarkerStyle
+MarkerType: TypeAlias = (
+    path.Path | MarkerStyle | str |  # str required for "$...$" marker
+    Literal[
+        ".", ",", "o", "v", "^", "<", ">",
+        "1", "2", "3", "4", "8", "s", "p",
+        "P", "*", "h", "H", "+", "x", "X",
+        "D", "d", "|", "_", "none", " ",
+        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+    ] | list[tuple[int, int]] | tuple[int, Literal[0, 1, 2], int]
+)
 """
 Marker specification. See :doc:`/gallery/lines_bars_and_markers/marker_reference`.
 """