patch 55731: StringBuilder logic in DataFormatter.cleanFormatForNumber

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1553248 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/ss/usermodel/DataFormatter.java

@@ -583,6 +583,7 @@ public class DataFormatter {
                         }
                         // Remove the character too
                         sb.deleteCharAt(i);
+                        i--;
                     }
                 }
             }
@@ -606,6 +607,7 @@ public class DataFormatter {
                     }
                     // Remove the _ too
                     sb.deleteCharAt(i);
+                    i--;
                 }
             }
         }