NcSelect: make same height and color as NcTextField

[GVodyanov]

☑️ Resolves

• Fix Inconsistent font and height of event resource inputs nextcloud/calendar#6155

🖼️ Screenshots

🏚️ Before	🏡 After

[GVodyanov]

Known issue we decided to procrastinate, on Firefox it looks like this:

(there are no opacity or box-shadows set)

[marcoambrosini]

Hi @GVodyanov, the height of these elements needs to be --default-clickable-area, the input fields will also shrink a bit soon

[GVodyanov]

Hi @GVodyanov, the height of these elements needs to be --default-clickable-area, the input fields will also shrink a bit soon

That's what it already should be set to actually @marcoambrosini

[susnux]

The color changes should only be applied to the placeholder, not the input element as the input text must stay main text color.

[GVodyanov]

I made the height of everything --default-clickable-area all the way through, does it seem ok?

[susnux]

Please remember to add correct labels:

1. State of the PR (e.g. 3. to review)
2. But more important the type of the PR: bug, enhancement or refactor this is needed for changelog generation.

Also always remember to backport to next (there is a TODO section in the PR template for this :) ).

[susnux]

/backport to next

[Antreesy]

Selector specificity either isn't big enough or scoped enough here (see leaked styles from server and viewer):

Not a part of this PR, of course, but something to consider

[susnux]

There is #5883