Improve quickfix to replace += operator with StringBuilder on left hand side with append() call

now works on java.lang.Appendable and splits concatenated strings into separate append calls

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/changeToAppend/before1.java

@@ -0,0 +1,6 @@
+// "Change to 'appendable.append(1)'" "true"
+class Test {
+  void appendable(StringBuilder appendable) throws IOException {
+    appendab<caret>le += 1;
+  }
+}