Fix bug in fetching injection group param (#4924)

* Fix bug in fetching injection group param

* try macos latest version (#4922) (#4926)

* try macos latest version

* move to update macos on build as well

Co-authored-by: Alex Nitz <alex.nitz@gmail.com>

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Co-authored-by: Alex Nitz <alex.nitz@gmail.com>

pycbc/events/triggers.py

@@ -227,7 +227,7 @@ def get_inj_param(injfile, param, ifo, args=None):
 
     inj = injfile["injections"]
     if param in inj.keys():
-        return inj["injections/"+param]
+        return inj[param][:]
 
     if param == "end_time_"+ifo[0].lower():
         return inj['end_time'][:] + det.time_delay_from_earth_center(