chore: update gitignore with checkstyle-idea file

Author: andrea-acampora

.gitignore

@@ -67,6 +67,7 @@ bin/
 .idea/protoeditor.xml
 .idea/kotlinc.xml
 .idea/vcs.xml
+.idea/checkstyle-idea.xml
 node_modules/
 .rpt2_cache/
 libraries/tools/kotlin-test-js-runner/lib/
@@ -78,4 +79,3 @@ outTmp/
 /kotlin-native/dist
 kotlin-ide/
 .vscode/*
-