fix: Improve big number time format UX

[etr2460]

🐛 Bug Fix
#1278 introduced the ability to show a timestamp for the value of big number, but as a result it overrode the default time format for the tooltip in big number trendline charts to a somewhat obscure (for americans) %d-%m-%Y %H:%M:%S format. This PR:

• makes the time formatter always visible (so that the big number trendline chart can always set it)
• Defaults to a format that's used globally, '%Y-%m-%d %H:%M:%S'

to: @krsnik93 @villebro @ktmud

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[codecov]

Codecov Report

Merging #1320 (466a9cc) into master (3c2d224) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1320   +/-   ##
=======================================
  Coverage   29.93%   29.94%           
=======================================
  Files         487      487           
  Lines        9838     9836    -2     
  Branches     1648     1648           
=======================================
  Hits         2945     2945           
+ Misses       6656     6654    -2     
  Partials      237      237           

Impacted Files	Coverage Δ
...et-chart-big-number/src/BigNumber/controlPanel.tsx	0.00% <ø> (ø)

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[krsnik93]

Hello @etr2460 thanks for the improvements and sorry for defaulting to a non-standard time format.

Changes are completely fine with me.

[ktmud]

YYYY-MM-DD for the win!

[ktmud]

But shouldn't the default be Smart Date? I don't think we even need to provide a default (empty value will be treated like Smart Date, hopefully) if the control is going to be displayed always.

[etr2460]

Hmm, if that's true then i agree removing it is correct. I'll make the change

[villebro]

LGTM