Fix NPE when handling empty CLOB values on Oracle 21c/23c

[pardhiv-krishna]

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Edits Oracle 21 and 23 platform files to fix NPE issue when inserting empty string value to a @Lob field of an entity.
Fixes #33573

[pardhiv-krishna]

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[pardhiv-krishna]

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• 1 FAT files were changed, added, or removed.

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• 4 product code files were changed.

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[ChithraMini]

LGTM - fix for the empty LOB issue