[bs-29] Support for XML configuration in groovy apps

Mixed .groovy and .xml now supported bia spring CLI, e.g.

$ spring samples/runner.groovy samples/runner.xml

[Fixes #48059037]

spring-bootstrap-cli/samples/runner.groovy

@@ -0,0 +1,10 @@
+package org.test
+
+class Runner implements CommandLineRunner {
+
+	void run(String... args) {
+		print "Hello World!"
+	}
+}
+
+