[JENKINS-74131] Extract inline JavaScript in FolderAuthorizationStrategyManagementLink/index.jelly

[yaroslavafenkin]

https://issues.jenkins.io/browse/JENKINS-74131

Along with CSP work I've also removed the calls to getValue(), which I assume could be leftovers from some framework that was removed.

Testing done

Before the change
After the change

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[yaroslavafenkin]

Changing the way function is declared allows me to call these the way I do on line 128 of this file (https://github.com/jenkinsci/folder-auth-plugin/pull/105/files#diff-acf15339083ce65e46e34d649d67bf58880b907daaddcb899dd15454fef2a978R128).
Otherwise I'd have had to add a specific class to every element that needs a handler (global, folder, agent) and attach each event handler separately.