refactor: introduce MathUtilModule, move is_same, add tests #1345

Job	Run time
Check format	1m 24s
Build	2m 16s
Smoke test	4m 40s
Test gnu fortran (ubuntu-22.04)	23m 38s
Test intel fortran (ubuntu-22.04, intel-classic, 2021.7)	23m 4s
Parallel testing (ubuntu-22.04)	9m 6s
Test gnu fortran (macos-12)	42m 5s
Test intel fortran (macos-12, intel-classic, 2021.7)	37m 47s
Parallel testing (macos-12)	19m 54s
Test gnu fortran (windows-2022)	31m 26s
Test intel fortran (windows-2022, intel-classic, 2021.7)	32m 9s
	3h 47m 29s

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