Removed armadillo from PauliOperator #89

Job	Run time
Linux CI	17m 7s
check-compilers (gcc:7, Debug)	15m 9s
check-compilers (gcc:7, Release)	16m 4s
check-distros (almalinux:9, Release)	17m 48s
check-compilers (gcc:8, Debug)	14m 56s
check-compilers (gcc:8, Release)	16m 59s
check-compilers (gcc:9, Debug)	14m 57s
check-compilers (gcc:9, Release)	17m 8s
check-compilers (gcc:10, Debug)	15m 25s
check-compilers (gcc:10, Release)	17m 40s
check-compilers (gcc:11, Debug)	15m 5s
check-compilers (gcc:11, Release)	17m 41s
check-compilers (gcc:12, Debug)	14m 37s
check-compilers (gcc:12, Release)	17m 57s
	3h 48m 33s

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