Updating splunk version to 7.3.0

Author: Brent Boe

Makefile

@@ -7,8 +7,8 @@ SPLUNK_ANSIBLE_BRANCH ?= develop
 SPLUNK_COMPOSE ?= cluster_absolute_unit.yaml
 # Set Splunk version/build parameters here to define downstream URLs and file names
 SPLUNK_PRODUCT := splunk
-SPLUNK_VERSION := 7.2.6
-SPLUNK_BUILD := c0bf0f679ce9
+SPLUNK_VERSION := 7.3.0
+SPLUNK_BUILD := 657388c7a488
 ifeq ($(shell arch), s390x)
 	SPLUNK_ARCH = s390x
 else