feat: removed unused html, moved html for better caching and remove d…

[schulmak]

Moved HTML which were just used by one credential type to the folder for better caching.
Reduced duplicate code and moved html which used by more than one credential type to /webapp. For the caching I would like to have them in the "src/main/resources" but I dont know how to do it without duplicate code. If you know how to do it would be nice if you could share it.
Removed src/main/webapp/help-msiPort.html since I could not find where it was used.
Removed the link from "src/main/webapp/help-subscriptionId.html" since it doesnt work anymore. Do you know a alternative link?
Renamed the file help-clientId.html in AzureImdsCredentials to help-clientIdImds.html since help-clientId.html is also in AzureCredentials.

Testing done

Build the plugin locally and opened the help boxes.

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[timja]

If you know how to do it would be nice if you could share it.

not aware, I would normally duplicate if its simple or do as you have done for more complex cases