[webUI] Drop placeholder text in forms

[kvndrsslr]

Problem statement:

• Currently, placeholder text which is the same as the label text is in every form field
• Does not add value, as label already has the information
• Has the potential to confuse users which text is their own and which is placeholder

Task:

• Drop placeholders

[kvndrsslr]

There are still some placeholders that get inserted when the user clicks on the radio buttons, please fix.