update CHANGELOG in preparation for new release

CHANGELOG.md

@@ -2,7 +2,11 @@ Below are the most important changes from each release.
 A more detailed list of changes is available in the corresponding milestones for each release in the Github issue tracker (https://github.com/googlefonts/fontbakery/milestones?state=closed).
 
 
-## Upcoming release: 0.10.3 (2023-Oct-??)
+## Upcoming release: 0.10.4 (2023-Nov-??)
+  - ...
+
+
+## Upcoming release: 0.10.3 (2023-Nov-02)
 ### New checks
 #### Added to the Google Fonts Profile
   - **EXPERIMENTAL - [com.google.fonts/check/glyphsets/shape_languages]:** This check uses a heuristic to determine which GF glyphsets a font supports. Then it checks the font for correct shaping behaviour for all languages in those glyphsets. (issue #4147)

Lib/fontbakery/profiles/googlefonts.py

@@ -840,7 +840,7 @@ def com_google_fonts_check_metadata_category(family_metadata):
     id="com.google.fonts/check/family/equal_codepoint_coverage",
     conditions=["are_ttf", "stylenames_are_canonical"],
     proposal="https://github.com/fonttools/fontbakery/issues/4180",
-    experimental="Since 2023-Oct-13",
+    experimental="Since 2023/Oct/13",
 )
 def com_google_fonts_check_family_equal_codepoint_coverage(ttFonts, config):
     """Fonts have equal codepoint coverage"""
@@ -3846,6 +3846,7 @@ def get_sibling_scripts(target):
         those glyphsets.
     """,
     proposal=["https://github.com/googlefonts/fontbakery/issues/4147"],
+    experimental="Since 2023/Nov/02",
 )
 def com_google_fonts_check_glyphsets_shape_languages(ttFont):
     """Shapes languages in all GF glyphsets."""