[FE]: summary visual improvements

[yuliya-ivaniukovich]

At the moment when we validate a file with large number of checks and only small amount of them failed we have the following minor issues:

1. Error sector in Pie chart is not visible at all
2. Success sector tooltip says 100% (our total displays 99%)
3. Success checks number in legend is formatted poorly (no thousands separator)

Tech notes:
[ ] instead of passing absolute numbers to chart let's calculate percents ourselves so that neither sector could be 100% if other values are not 0 (cover this calculations with unit tests)
[ ] let's customize chart tooltip as following:

99.99% passed
(1,700,000 checks)

0.01% errors
(15 checks)

Pie center still should display rounded(floored) 99% in case above.

PS: precision of 2 decimals is just an example, we can adjust it so that minimal sector was displayed in Google Chart.