Improved element positioning

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Short description of what this resolves:

I propose some small improvements to element positioning in the ProtonMail Web Application V4

0608764: 1/4rem more margin on the left side of the label collection
e1c0135: 1/2em more padding for a minimized composer window on the top and bottom of the subject line

0608764

labels

e1c0135

Before:

After: