Update matplotlib docs wg meeting schedule (#850)

* Update matplotlib docs wg meeting schedule

Cancels April 3rd meeting.

* whitespace nitpick

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Co-authored-by: Brigitta Sipőcz <b.sipocz@gmail.com>

Author: melissawm

calendars/matplotlib.yaml

@@ -51,7 +51,7 @@ events:
 
       Meeting notes: https://hackmd.io/@matplotlib/dwg
 
-    begin: 2023-12-15 17:00:00 +00:00
-    end: 2023-12-15 18:00:00 +00:00
+    begin: 2026-04-17 17:00:00 +00:00
+    end: 2026-04-17 18:00:00 +00:00
     url: https://us06web.zoom.us/j/81285851006?pwd=Tks2QjRkNWh5NGw0TmU1RUwwOVluZz09
     ics: RRULE:FREQ=WEEKLY;BYDAY=FR;INTERVAL=2