build: minor python3 updates

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Idbc9d0b2ff60fad2fff9d013ff19a4208f4d8161
diff --git a/extensions/openpower-pels/registry/run-ci.sh b/extensions/openpower-pels/registry/run-ci.sh
index 4868f9b..c0bcc61 100644
--- a/extensions/openpower-pels/registry/run-ci.sh
+++ b/extensions/openpower-pels/registry/run-ci.sh
@@ -1,3 +1,3 @@
-/usr/bin/env python extensions/openpower-pels/registry/tools/process_registry.py \
+/usr/bin/env python3 extensions/openpower-pels/registry/tools/process_registry.py \
 -v -s extensions/openpower-pels/registry/schema/schema.json \
 -r extensions/openpower-pels/registry/message_registry.json