[Enhancement] Ignore union type tag when converting avro to json (backport #52973)

[mergify]

Why I'm doing:

schema:

 {
    "type": "record",
    "name": "User",
    "fields": [
        {"name": "id", "type": "int"},
        {"name": "name", "type": "string"},
        {"name": "email", "type": ["null",
                                   {
                                       "type": "record",
                                       "name": "email2",
                                       "fields": [
                                           {
                                               "name": "x",
                                               "type" : ["null", "int"]
                                           },
                                           {
                                               "name": "y",
                                               "type": ["null", "string"]
                                           }
                                       ]
                                   }
                                  ]
         }
    ]
 }

avro avro_value_to_json result:
{"id": 1, "name": "Alice", "email": {"email2": {"x": {"int": 1}, "y": {"string": "[email protected]"}}}}

What I'm doing:

add a new function to convert avro values to JSON strings while ignoring union type tags.
{"id":1,"name":"Alice","email":{"x":1,"y":"[email protected]"}}

add a new config avro_ignore_union_type_tag and modify existing functions to use this new conversion method based on the config.

Fixes #issue

What type of PR is this:

• BugFix
• Feature
• Enhancement
• Refactor
• UT
• Doc
• Tool

Does this PR entail a change in behavior?

• Yes, this PR will result in a change in behavior.
• No, this PR will not result in a change in behavior.

If yes, please specify the type of change:

• Interface/UI changes: syntax, type conversion, expression evaluation, display information
• Parameter changes: default values, similar parameters but with different default values
• Policy changes: use new policy to replace old one, functionality automatically enabled
• Feature removed
• Miscellaneous: upgrade & downgrade compatibility, etc.

Checklist:

• I have added test cases for my bug fix or my new feature
• This pr needs user documentation (for new or modified features or behaviors)
  • I have added documentation for my new feature or new function
• This is a backport pr

Bugfix cherry-pick branch check:

• I have checked the version labels which the pr will be auto-backported to the target branch
  • 3.4
  • 3.3
  • 3.2
  • 3.1
  • 3.0
  • 2.5

---

This is an automatic backport of pull request #52973 done by [Mergify](https://mergify.com). ## Why I'm doing: schema: ``` { "type": "record", "name": "User", "fields": [ {"name": "id", "type": "int"}, {"name": "name", "type": "string"}, {"name": "email", "type": ["null", { "type": "record", "name": "email2", "fields": [ { "name": "x", "type" : ["null", "int"] }, { "name": "y", "type": ["null", "string"] } ] } ] } ] } ```

avro avro_value_to_json result:
{"id": 1, "name": "Alice", "email": {"email2": {"x": {"int": 1}, "y": {"string": "[email protected]"}}}}

What I'm doing:

add a new function to convert avro values to JSON strings while ignoring union type tags.
{"id":1,"name":"Alice","email":{"x":1,"y":"[email protected]"}}

add a new config avro_ignore_union_type_tag and modify existing functions to use this new conversion method based on the config.

Fixes #issue

What type of PR is this:

• BugFix
• Feature
• Enhancement
• Refactor
• UT
• Doc
• Tool

Does this PR entail a change in behavior?

• Yes, this PR will result in a change in behavior.
• No, this PR will not result in a change in behavior.

If yes, please specify the type of change:

• Interface/UI changes: syntax, type conversion, expression evaluation, display information
• Parameter changes: default values, similar parameters but with different default values
• Policy changes: use new policy to replace old one, functionality automatically enabled
• Feature removed
• Miscellaneous: upgrade & downgrade compatibility, etc.

Checklist:

• I have added test cases for my bug fix or my new feature
• This pr needs user documentation (for new or modified features or behaviors)
  • I have added documentation for my new feature or new function
• This is a backport pr