fix o4b end date

https://observing.docs.ligo.org/plan/

LIGO, Virgo, and KAGRA have adopted a change to the end date for the O4 observing run, which previously had been set as February 2025. It has been decided to extend the O4 run, to allow for greater preparation of upgrade hardware that will be installed for O5. The new end date for O4 is 9 June 2025.

gracedb/search/constants.py

@@ -21,9 +21,8 @@ RUN_MAP = {
             # https://observing.docs.ligo.org/plan/
             # The LIGO Hanford (LHO), LIGO Livingston (LLO), and Virgo detectors transitioned
             # to the regular observing run O4b at 15:00 UTC on 10 April 2024. O4b will run
-            # until February 2025 (FIXME specific date TBD), with no further planned breaks
-            # in observing.
-            "O4b": (1396796418, 1423238418),
+            # until 9 June 2025 (assuming 15:00 UTC but FIXME later).
+            "O4b": (1396796418, 1433516418),
             # O4a started May 24, 2023 1500UTC and ended Jan 16, 2024 1600UTC
             "O4a": (1368975618, 1389456018),
           },