Make JDBCRepositorySQLLoader avoid using Path#toFile in GraalVM Native Image

[linghengqian]

For #29000.

Changes proposed in this pull request:

• Make JDBCRepositorySQLLoader avoid using Path#toFile in GraalVM Native Image. Refer to Calling java.nio.file.Path#toFile under Native Image will result in java.lang.UnsupportedOperationException oracle/graal#7804 .
• Also for Make ShardingSphere Proxy in GraalVM Native Image form available #21347.

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