bug 1512499 - handle psutil returning None for physical_cores. r=froydnj

psutil has a bug on arm systems where it will return None for physical_cores:
giampaolo/psutil#1359

This causes us to generate invalid telemetry data which raises an error. Fix
this by simply omitting the field in this case.

Differential Revision: https://phabricator.services.mozilla.com/D14969

UltraBlame original commit: be66f8877e465637de546fd3a94a55009e74f973

python/mozbuild/mozbuild/telemetry.py

@@ -1492,12 +1492,7 @@
 (
 )
 
-info
-[
-'
 physical_cores
-'
-]
 =
 psutil
 .
@@ -1508,6 +1503,22 @@
 False
 )
 
+if
+physical_cores
+is
+not
+None
+:
+
+info
+[
+'
+physical_cores
+'
+]
+=
+physical_cores
+
 #
 total
 on