Remove outdated info sections and content from primary user stores

[RusJaI]

Description:

check the $subject in primary user stores main page and read only user stores, active directory user stores pages.
The links to the sections are not working in read-only and read-write LDAP docs.
There are some mentions of embedded LDAP of WSO2 IS which is not applicable further.

[RusJaI]

Update [2024-10-31]

PR was added for 4.4.0 branch.

This is included as a separate commit in the same PR, hence is on hold due to #8439 (comment)

[RusJaI]

Added the PRs for other 4.x versions.

Please find the List of PRs :
4.4.0 : #8601, #8635
4.3.0 : #8631
4.2.0: #8620

Master : #8630

Note : Since APIM 4.0.0 and 4.1.0 supports IS 5.11.0 which has the inbuilt read write LDAP, the documentation have to be modified accordingly.

4.1.0 : #8634
4.0.0: #8636

There are some broken doc links in primary user store main page of APIM 4.3.0 onwards.
4.4.0 : #8638
Added the fix in the previously added PRs for other applicable versions