[MPMD-354] - Upgrade to PMD 6.49.0

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https://issues.apache.org/jira/browse/MPMD-354

Following this checklist to help us incorporate your
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• Make sure there is a JIRA issue filed
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• Each commit in the pull request should have a meaningful subject line and body.
• Format the pull request title like [MPMD-XXX] - Subject of the JIRA Ticket,
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