Fixing Lucene912Codec Issue with BWC for Lucene 10.0.1 upgrade

[Vikasht34]

Description

As per Lucene 10.0.1 upgrade, Path of Lucene912Codec has been changed and which is breaking BWC tests.

https://github.com/apache/lucene/blob/main/lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene912/Lucene912Codec.java

This PR aims to fix the path to correct Lucene912Codec.

Related Issues

None

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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[martin-gaievski]

it looks like opensearch-knn-test-fixtures needs to consume latest corre main with lucene 10

/home/runner/work/k-NN/k-NN/src/main/java/org/opensearch/knn/index/codec/KNNCodecVersion.java:16: error: package org.apache.lucene.backward_codecs.lucene912 does not exist
import org.apache.lucene.backward_codecs.lucene912.Lucene912Codec;

[Vikasht34]

it looks like opensearch-knn-test-fixtures needs to consume latest corre main with lucene 10

/home/runner/work/k-NN/k-NN/src/main/java/org/opensearch/knn/index/codec/KNNCodecVersion.java:16: error: package org.apache.lucene.backward_codecs.lucene912 does not exist
import org.apache.lucene.backward_codecs.lucene912.Lucene912Codec;

Yes ...Agree ...We need to change to alpha !! lots of things started breaking ..This Pr would be updated with all latest changes.