changes.txt: retrospectively added two changelog items for 1.25.2.

Author: julian-smith-artifex-com

changes.txt

@@ -11,6 +11,10 @@ Change Log
   * **Fixed** `4186 <https://github.com/pymupdf/PyMuPDF/issues/4186>`_: Incorrect handling of JPEG with color space CMYK image extraction
   * **Fixed** `4225 <https://github.com/pymupdf/PyMuPDF/issues/4225>`_: pixmap.pil_save() fails due to colorspace definition
   * **Fixed** `4232 <https://github.com/pymupdf/PyMuPDF/issues/4232>`_: Incorrect Font style and Size
+  * **Fixed** `4195 <https://github.com/pymupdf/PyMuPDF/issues/4195>`_: Pixmaps that are inverted and have an alpha channel are not rendered properly
+  * **Fixed** `4162 <https://github.com/pymupdf/PyMuPDF/issues/4162>`_: Got AttributeError, when tried to add Signature field
+
+
 
 * Other: