Migrate LDAP example to JUnit 5

[divyajnu08]

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[mp911de]

You might want to check and update your Git settings. The author Author: divya_jnu08 <divya@virtueanalytics.com> doesn't refer to your GitHub profile (see the commit 48359ee), likely because the email address isn't associated with your GitHub profile.

[mp911de]

Thank you for your contribution. That's merged and polished now.