Feat: Endpoint for msadmins to get all applications via organizations

[oscar-ekeyekwu]

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• Run npm run lint to find errors in code syntax/format
• Run npm run lint:fix to fix all auto-fixable errors in source code and auto-format with prettier
• Ensure you fix any linting errors displayed after running any of the above commands

What does this PR do?

Fixes #455 (replace issue_number with the issue number this PR solves)

Summarise the main tasks handled in the pull request

description of Task to be completed?

• Create controller method
• Write validation Rules
• Write tests for the endpoint

How should this be manually tested?

Give bullet point instructions on how to setup the code and test it manually (Assume no prior experience on JS or code)

Any background context you want to provide?

Any pertinent information that should be considered

What is the link to the issue on Github?

Issue #455

Questions:

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