[BUG] The index setting "ignore_malformed" is not working properly

[hauck-jvsh]

Describe the bug
The "ignore_malformed" option should allow inconsistent data to be indexed, losing only the malformed fields, but it is ignoring the entire item.

To Reproduce

1. Create an empty index with the setting "ignore_malformed": "true".
2. insert the following data {
   "name":"test 1",
   "other_field":"string content"
   }
3. insert the following data {
   "name":"test 2",
   "other_field":{"comment":"object content","size":2}
   }

Expected behavior
In this situation the second item should be indexed only the field "other_field" should be missed, but the hole item is lost.

Host/Environment (please complete the following information):

• OS: centos 8
• Version 2.1

Additional context
I'm using this to index a lot of unstructured data, and sometimes a few fields are invalid, but it shouldn't lose the valid fields.

[hauck-jvsh]

Should I try to make a fix?

[dblock]

@hauck-jvsh Please!

[hauck-jvsh]

Sorry for the delay, but I finally get some time to work on this.

[hauck-jvsh]

Should I close this?

[dblock]

Yep, assuming #4494 closes this.