Fixed Equinox and Solstice dates in Calculator
Summary:
This patch uses a revised version of the algorithm from Astronomical algorithms - Jean Meeus to calculate the correct dates of Equinox and Solstice in Calculator.
BUG: 387929
Reviewers: mutlaqja
Reviewed By: mutlaqja
Subscribers: mutlaqja, kde-edu
Differential Revision: https://phabricator.kde.org/D27413