THRIFT-5571: add metadata map building to kotlin generator (#2584)

diff --git a/lib/kotlin/Makefile.am b/lib/kotlin/Makefile.am
index 6a99628..f57fc33 100644
--- a/lib/kotlin/Makefile.am
+++ b/lib/kotlin/Makefile.am
@@ -22,7 +22,7 @@
 all-local:
 	$(GRADLE) $(GRADLE_OPTS) assemble \
 		-Pthrift.version=$(PACKAGE_VERSION) \
-    -Pthrift.compiler=$(THRIFT) \
+		-Pthrift.compiler=$(THRIFT) \
 		--console=plain
 
 clean-local: