Fix inconsistent inflection of Ldap module

What does this MR do?

Changes modules to all use Ldap instead of LDAP. We need to do this to prepare us for the switch to Zeitwerk. It expects modules to be inflected the same way throughout the application.

It was actually easier to change Ldap to LDAP but controllers don't work because the router uses ActiveSupport inflections.

We could change the ActiveSupport inflection for this but it would affect multi-word classes like LdapSyncWorker and having to change all these would be a larger change.

This was extracted from !20521 (merged) for easier review

Related to #197345 (closed)

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Does this MR meet the acceptance criteria?

Conformity

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• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
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Security

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