test_diag_integral: Avoid I/O unit 100 #66

Job	Run time
build (-DOPENMP=on, -DCMAKE_BUILD_TYPE=Release)	11m 24s
build (-DOPENMP=on, -DCMAKE_BUILD_TYPE=Debug)	3m 28s
build (-DOPENMP=on, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Release)	12m 47s
build (-DOPENMP=on, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Debug)	4m 1s
build (-DOPENMP=on, -DWITH_YAML=on, -DCMAKE_BUILD_TYPE=Release)	12m 12s
build (-DOPENMP=on, -DWITH_YAML=on, -DCMAKE_BUILD_TYPE=Debug)	3m 34s
build (-DOPENMP=on, -DWITH_YAML=on, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Release)	12m 40s
build (-DOPENMP=on, -DWITH_YAML=on, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Debug)	4m 0s
build (-DOPENMP=off, -DCMAKE_BUILD_TYPE=Release)	11m 29s
build (-DOPENMP=off, -DCMAKE_BUILD_TYPE=Debug)	3m 30s
build (-DOPENMP=off, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Release)	12m 34s
build (-DOPENMP=off, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Debug)	3m 47s
build (-DOPENMP=off, -DWITH_YAML=on, -DCMAKE_BUILD_TYPE=Release)	11m 53s
build (-DOPENMP=off, -DWITH_YAML=on, -DCMAKE_BUILD_TYPE=Debug)	3m 44s
build (-DOPENMP=off, -DWITH_YAML=on, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Release)	13m 42s
build (-DOPENMP=off, -DWITH_YAML=on, -DUSE_DEPRECATED_IO=on, -DCMAKE_BUILD_TYPE=Debug)	4m 7s
	2h 8m 52s

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