Fix Ignite connector to use standard SQL identifier quoting

[yadavay-amzn]

Fixes #29303.

Problem

The Ignite connector uses backtick as identifier quote character, but Ignite SQL does not recognize backticks. This prevents creating tables with mixed-case identifiers.

Fix

Two changes:

1. Change identifier quote from backtick to double-quote in IgniteClient. Ignite SQL requires double-quotes for case-sensitive identifiers per SQL standard.

2. Override getRemoteIdentifiers() to force storesUpperCaseIdentifiers=true. Ignite stores unquoted identifiers as uppercase, but its JDBC driver does not report this correctly via DatabaseMetaData.storesUpperCaseIdentifiers(). The override ensures DefaultIdentifierMapping uppercases identifiers before quoting, so Trino's lowercase public becomes "PUBLIC" when sent to Ignite. This is the same pattern used by DruidJdbcClient.

Why the prior attempt (#29307) was closed

The prior contributor noted that swapping the quote character breaks schema resolution ("public" != PUBLIC). They missed that the IdentifierMapping infrastructure handles this, but, only when storesUpperCaseIdentifiers() returns true, which Ignite's driver does not report correctly. The getRemoteIdentifiers() override fixes this.

Testing

All Ignite plugin tests pass locally (361 tests):

• TestIgniteClient (5/5) -- SQL generation with double-quote quoting
• TestIgniteCaseInsensitiveMapping (10/10) -- case-insensitive identifier resolution
• TestIgniteConnectorTest (346/346) -- full connector integration tests

[github-actions]

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[ebyhr]

Could you fix CI failures?

[yadavay-amzn]

@ebyhr I fixed the test failures and pushed a new commit. CI is re-running for theses and i verified that the tests pass locally now.
Since this is my first trino change, i need my CLA verification to be approved so the CI might continue to fail until that is approved