Update smithy-gradle-plugin Version to 1.2.0 (#2496)

Co-authored-by: Smithy Automation <[email protected]>

Author: smithy-automation

gradle.properties

@@ -1,4 +1,4 @@
 org.gradle.configureondmand=true
 org.gradle.jvmargs='-Dfile.encoding=UTF-8'
 org.gradle.parallel=true
-smithyGradleVersion=1.1.0
+smithyGradleVersion=1.2.0