fix: remove unused 'charset' in generate schema encoders

[nglehuy]

Remove unused 'charset' in generate schema encoders

Description

• remove unused 'charset' in generate schema encoders
• update element_type in ArrayField of postgres to be uppercase

Motivation and Context

Error when using get_schema_sql on ArrayField with default value

self = <tortoise.backends.asyncpg.schema_generator.AsyncpgSchemaGenerator object at 0x106f28440>, default = [0, 0, 0, 0]

    def _escape_default_value(self, default: Any):
        if isinstance(default, bool):
            return default
>       return encoders.get(type(default))(default)  # type: ignore
E       TypeError: escape_sequence() missing 1 required positional argument: 'charset'

Encoders functions should accept the same number of arguments

How Has This Been Tested?

Update tests/schema/models_postgres_index.py, tests/schema/test_generate_schema.py and run make test

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added the changelog accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[henadzit]

Thank you for working on this! I added a single comment.

[henadzit]

The Index model is used for testing indexes specifically and there is no index on array in this case. It would be better to use another model for testing arrays.

It might make sense to add a new test or find a more suitable one.

[coveralls]

Pull Request Test Coverage Report for Build 12378120829

Details

• 7 of 9 (77.78%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.2%) to 90.647%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tortoise/converters.py	6	8	75.0%

Totals
Change from base Build 12342471369:	0.2%
Covered Lines:	6322
Relevant Lines:	6868

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💛 - Coveralls